typo in hinge.svg

Black 6mm rectangle should have a height of 22.56, with the lower hole 6mm from the bottom, and the top hole 5.28 from the top. It was off by 0.28mm so hardly noticable with the kerf of the laser, but we may as well make it exact.
Add redrawn STEP files
2025-12-05 23:20:26 -08:00 · 2025-10-08 12:07:19 +01:00 · 2025-10-08 11:55:02 +01:00 · 2025-10-08 11:54:08 +01:00 · 2025-10-08 11:24:02 +01:00 · 2025-10-08 11:08:22 +01:00
65 changed files with 7476 additions and 220 deletions
--- a/.gitattributes
+++ b/.gitattributes
@@ -0,0 +1 @@
+*/.settings/language.settings.xml filter=eclipse_env_hash
--- a/brightness-curve.htm
+++ b/brightness-curve.htm
@@ -1,16 +1,20 @@
 <!doctype html>

 <canvas width=800 height=600 style='position:relative;'></canvas>
-<pre></pre>
+<br>
+<textarea style="width:300px;height:100px" oninput='parse()'></textarea>
+<span style='position:absolute;pointer-events:none;font-family:monospace;'></span>

 <script>
-pre = document.querySelector('pre')
+pre = document.querySelector('textarea')
+span = document.querySelector('span')
 canvas = document.querySelector('canvas')
 ctx = canvas.getContext('2d')

 w = canvas.width; h = canvas.height;
 gw = w-50; gh = h-50
 gx=25; gy=25
+b={x:0,y:0}

 curve = [
 [0, 0],
@@ -33,7 +37,9 @@ function circle(x,y) {
  ctx.stroke(); 
 }
  ctx.font = '18px Courier, monospace';
-function draw(){
+function draw(wb){
+  b=canvas.getBoundingClientRect()
+
  ctx.clearRect(0,0,w,h)
  ctx.fillStyle='rgba(1,1,1,0.05)'
  ctx.fillRect(gx,gy,gw,gh)
@@ -56,11 +62,11 @@ function draw(){
    if (i) line( curve[i-1][0], curve[i-1][1], curve[i][0], curve[i][1] )
  }

+  if (wb) return;
  s=""
  for (let i=0;i<curve.length;i++)
-  //  s+='{'+Math.round(curve[i][0]*4095)+', 4095-'+Math.round(curve[i][1]*4095)+'},\n'
    s+= "BS"+(i+1)+" = "+ Math.round(curve[i][0]*4095)+ ',' + Math.round(curve[i][1]*4095)+"\n"
-  pre.textContent = s
+  pre.value = s
 }

 function distance(x1,y1,x2,y2){
@@ -87,27 +93,95 @@ function clamp(x,y,i){
  return [Math.min(maxx,Math.max(minx,x)),Math.min(1,Math.max(0,y))]
 }

+function highlight(e){
+  let x = (e.pageX-gx-b.x)/gw;
+  let y = 1-(e.pageY-gy-b.y)/gh;
+  if (x<0.0 || x>1.0 || y<0.0 || y>1.0) {
+    span.textContent="";
+  } else {
+    let out = single(x)
+    span.textContent=Math.round(x*4095)+","+Math.round(out*4095);
+    span.style.left=e.pageX+"px"
+    span.style.top=((1-out)*gh+gy+b.y)+"px"
+  }
+}
+document.onmousemove=highlight
+
 canvas.onmousedown=function(e){
  e.preventDefault()
-  let x = (e.layerX-gx)/gw;
-  let y = 1-(e.layerY-gy)/gh;
+  let x = (e.pageX-gx-b.x)/gw;
+  let y = 1-(e.pageY-gy-b.y)/gh;
+  span.textContent="";

  let i = nearestPoint(x,y)

  curve[i] = clamp(x,y,i)
  document.onmousemove=function(e){
-    let x = (e.layerX-gx)/gw;
-    let y = 1-(e.layerY-gy)/gh;
+    let x = (e.pageX-gx-b.x)/gw;
+    let y = 1-(e.pageY-gy-b.y)/gh;
    curve[i] = clamp(x,y,i)
    draw()
  }
  document.onmouseup=function(e){
-    document.onmousemove=null
+    document.onmousemove=highlight
    document.onmouseup=null
  }
  draw()
 }


+touch={};
+canvas.addEventListener("touchstart",function(e){
+  if (e.touches.length>1) return;
+  for (let t of e.changedTouches) {
+    let x = (t.pageX-gx-b.x)/gw
+    let y = 1-(t.pageY-gy-b.y)/gh
+
+    let i = nearestPoint(x,y)
+    curve[i] = clamp(x,y,i)
+    touch = {id:t.identifier,i}
+  }
+  e.preventDefault();
+  draw()
+},true);
+canvas.addEventListener("touchmove",function(e){
+  for (let t of e.changedTouches) {
+    if (touch.id == t.identifier) {
+      let x = (t.pageX-gx-b.x)/gw
+      let y = 1-(t.pageY-gy-b.y)/gh
+
+      curve[touch.i] = clamp(x,y,touch.i)
+    }
+  }
+  draw()
+},true);
+
+
+function parse(){
+  var lines = pre.value.split("\n");
+  for (let line of lines) {
+    let m = line.match(/^BS([1-5]) = (\d+),(\d+)$/)
+    if (!m || m[2]>4095 || m[3]>4095) continue;
+    curve[m[1]-1]=[m[2]/4095, m[3]/4095]
+  }
+  draw(1)
+}
+
+
+function single(inp){
+  let i;
+  for (i=1; i< curve.length-1; i++){
+    if (curve[i][0] > inp) break;
+  }
+  let factor = (inp - curve[i-1][0]) / (curve[i][0] - curve[i-1][0]);
+  let out = curve[i-1][1]*(1.0-factor) + curve[i][1]*factor;
+
+  if (out>1.0 || isNaN(out)) out=1.0;
+  else if (out<0.0) out=0.0;
+
+  return out
+}
+
 draw()
-</script>
+
+</script>
--- a/cad/antenna-case/antenna-case.scad
+++ b/cad/antenna-case/antenna-case.scad
@@ -0,0 +1,85 @@
+module antenna(){
+    rotate([90,0,0])cylinder(h=22,r=2,$fn=100);
+    translate([-23.2/2,0,-1])cube([23.2,23.2,3]);
+    translate([-21/2,1,-2])cube([21,21,6.5]);
+    translate([-21/2,1,-2])cube([21,22,3]);
+    translate([-20/2,0,-2])cube([20,3,3]);
+    translate([0,23.2/2,0])cylinder(h=4.8,r=7);
+}
+
+
+module caseb_outer() {
+    rotate([90,0,0])cylinder(h=17,r=3.2,$fn=6);
+    translate([-25/2,-1,-2.771])cube([25,25,2.771]);
+
+    translate([-10,23.5,-1])cube([20,1,1]);
+    translate([-10,-1.4,-1])cube([20,1,1]);
+}
+module caseb() difference(){
+    caseb_outer();
+    antenna();
+    translate([-25,-25,0])cube([50,60,5]);
+    
+    translate([11.5,-2,-3])rotate([0,30,0])cube([5,30,5]);
+    translate([-15.5,-2,-6])rotate([0,-30,0])cube([5,30,5]);
+    
+    translate([2.8,-17,-2])cube([10,3,4]);
+    translate([-12.8,-17,-2])cube([10,3,4]);
+}
+
+
+module caset_outer(){
+    rotate([90,0,0])cylinder(h=17,r=3.2,$fn=6);
+    translate([-25/2,-1,0])cube([25,25,2.771]);
+
+    translate([-24/2,-0.5,0])cube([24,24,5.2]);
+    translate([-24.4/2,-0.7,0])cube([24.4,24.4,3]);
+}
+
+module caset_notabs() difference(){
+    caset_outer();
+    antenna();
+    translate([-25,-25,-5])cube([50,60,5]);
+}
+module tabprofile() difference(){
+    translate([-10,24.0,-2.5])cube([20,1.2,4.0]);
+    translate([-10,23.5,-1.2])cube([20,1,1.2]);
+    
+    translate([-10,24.3,-2.6])rotate([-30,0,0])cube([20,1,2]);
+    translate([-10,25.3,0.0])rotate([30,0,0])cube([20,1,2]);
+}
+
+module caset(){
+    caset_notabs();
+    tabprofile();
+    difference(){
+        translate([0,23,0])scale([1,-1,1]) tabprofile();
+        translate([-3.5,-2.5,-2.6])cube([7,5,5]);
+    }
+    difference(){
+        intersection(){
+            translate([0,-14,0])rotate([90,0,0])cylinder(h=3,r=4.2,$fn=6);
+            translate([-5,-20,-1.5])cube([10,10,4.271]);
+        }
+        translate([0,-14,0])rotate([90,0,0])cylinder(h=4,r=3.2,$fn=6);
+        
+    }
+}
+
+//difference(){
+color("#8f8") caset();
+  //  translate([0,-25,-10])cube([50,60,20]);
+//}
+
+//render()
+//caseb();
+
+
+difference(){
+    //color("#f88")caseb();
+    //translate([-25,10,-10])cube([50,60,20]);
+}
+
+
+
+%antenna();
--- a/cad/antenna-case/caseb.stl
+++ b/cad/antenna-case/caseb.stl
--- a/cad/antenna-case/caset.stl
+++ b/cad/antenna-case/caset.stl
--- a/cad/colons.scad
+++ b/cad/colons.scad
@@ -0,0 +1,212 @@
+$fn=100;
+
+revD = true; // set false to generate Rev C parts
+
+
+h=revD ? 34.2 : 34.4;
+w=12.0;
+d=10.5;
+
+t_side=1;
+t_front=1;
+t_top=1.5;
+
+tabwidth=5;
+tabheight=2.9;
+
+led_height=3;
+led_dia=3.15;
+
+ldr_height=1.9;
+
+// colon positions
+deltaV=11.3;
+deltaH=1.85;
+
+c1x= w/2-deltaH/2;
+c2x= w/2+deltaH/2;
+c1y= h/2+deltaV/2;
+c2y= h/2-deltaV/2;
+
+//latch size, depth and margin
+ls=5.5;
+ld=0.6;
+lmv=0.15;
+lmh=0.6;
+
+module latchMale(){
+    translate([w/2-ls/2,-ld,d/2-ls/2])cube([ls,ld,ls]);
+}
+module latchFemale(){
+    //difference(){
+    //    translate([0,-ld,0])cube([w,ld,d]);
+        translate([w/2-ls/2-lmh,-ld*2,d/2-ls/2-lmv])cube([ls+lmh*2,ld*2,ls+lmv*2]);
+    //}
+}
+
+module sideCutout(){
+    sc_r = 7;
+    sc_i = 12;
+    translate([-1,sc_i,11])rotate([0,90,0])cylinder(h=w+2,r=sc_r);
+    translate([-1,h-sc_i,11])rotate([0,90,0])cylinder(h=w+2,r=sc_r);
+    translate([-1,sc_i,11])rotate([0,90,0])cube([sc_r,h-sc_i*2,w+2]);
+}
+
+module colon(){
+    difference(){
+        union(){
+            difference() {
+                cube([w,h,d]);
+                translate([t_side,t_top,t_front])cube([w-t_side*2,h-t_top*2,d]);
+
+                sideCutout();
+            }
+            translate([c1x,c1y,0])cylinder(led_height,d=5);
+            translate([c2x,c2y,0])cylinder(led_height,d=5);
+            tab();
+            translate([w,h,0])rotate([0,0,180]) tab();
+        }
+        translate([c1x,c1y,-1])cylinder(11,d=led_dia);
+        translate([c2x,c2y,-1])cylinder(11,d=led_dia);
+    }
+}
+
+module switchcover(){
+    h=34.6;
+    difference(){
+        union(){
+            difference() {
+                cube([w,h,d]);
+                translate([t_side,t_top,t_front])cube([w-t_side*2,h-t_top*2,d]);
+            }
+            tab();
+            translate([w,h,0])rotate([0,0,180]) tab();
+            latchMale();
+        }
+        translate([w/2,h/2-4.5,-1])cylinder(11,d=3.5);
+        translate([w/2,h/2+4.5,-1])cylinder(11,d=3.5);
+        translate([0,-ld,0])magnet();
+        translate([w/2-2,0.3,6])rotate([-20,0,0])cube([4,3,4]);
+    }
+    translate([0,-ld,0])magnetHolder();
+    
+    //latchMale();
+    //latchFemale();
+}
+
+module magnet(){
+    translate([w/2,4.0,d/2])rotate([90,0,0])cylinder(h=3.5,d=4.1);
+}
+
+module magnetHolder(){
+    cutaway=0;
+    difference(){
+        translate([w/2-3,1,d/2-4.5])cube([6,3.5-cutaway,5]);
+        magnet();
+    }
+    translate([w/2-3,4,5.75])rotate([-20,0,0])cube([6,0.5,2]);
+    translate([w/2+2.1,3.22,5.5])rotate([-45,0,0])cube([0.9,0.5,1.5]);
+    translate([w/2-3,3.22,5.5])rotate([-45,0,0])cube([0.9,0.5,1.5]);
+}
+ldr_pad=0.07;
+module ldr(){
+    h=34.6;
+    difference(){
+        union(){
+            difference() {
+                cube([w,h,d]);
+                translate([t_side,t_top,t_front])cube([w-t_side*2,h-t_top*2,d]);
+            }
+            tab();
+            translate([w,h,0])rotate([0,0,180]) tab();
+            translate([w/2-2.5,h/2+1.45,0.5]){
+                cube([5.0,1.0,2]);
+                cube([5.0,1.3,1.6]);
+            }
+            translate([w/2-2.5,h/2-2.45,0.5])cube([5.0,1.0,2]);
+            translate([w/2-2.5,h/2-2.75,0.5])cube([5.0,1.3,1.6]);
+            
+        }
+        translate([w/2,h/2,-1]) intersection(){
+            cylinder(ldr_height+1,r=2.5+ldr_pad);
+            translate([-5,-4.0/2-ldr_pad,0])cube([10,4.0+ldr_pad*2,ldr_height+1]);
+        }
+        translate([w-1,1.5+3.58,d-2])cube([1,8,2]);
+        translate([0,ld,0])magnet();
+        //translate([w/2-2,0.9+ld,6])rotate([-20,0,0])cube([4,3,4]);
+        translate([0,ld,0])latchFemale();
+    }
+    magnetHolder();
+
+}
+
+module vtt9812fh(){
+    h=34.6;
+    difference(){
+        union(){
+            difference() {
+                cube([w,h,d]);
+                translate([t_side,t_top,t_front])cube([w-t_side*2,h-t_top*2,d]);
+            }
+            tab();
+            translate([w,h,0])rotate([0,0,180]) tab();
+
+            translate([w/2,h/2,0]) cylinder(d=7,h=2.8);
+        }
+        translate([w/2,h/2,-1]) intersection(){
+            cylinder(d=5,h=5);
+
+        }
+        translate([w-1,1.5+3.58,d-2])cube([1,8,2]);
+        translate([0,ld,0])magnet();
+        translate([0,ld,0])latchFemale();
+    }
+    magnetHolder();
+
+}
+
+module tab(){
+    difference(){
+        translate([w/2-tabwidth/2,0,d]) {
+            cube([tabwidth,1.5,tabheight-1]);
+            translate([0,0,1.6])cube([tabwidth,2,tabheight-1-1.6]);
+            translate([0,1.0,tabheight-1])rotate([0,90,0])cylinder(h=tabwidth,r=1.0);
+        }
+        translate([0,1.5,d]) cube([w,2,1.6]);
+    }
+}
+
+module ldrFitTest() {
+    cutaway=1;
+    intersection(){
+        ldr();
+        translate([1,12,0]) cube([10-cutaway*5,10,5]);
+    }
+}
+
+
+/*
+intersection(){
+    //ldr();
+    switchcover();
+
+    translate([0,-2,0])cube([w/2,40,20]);
+}
+//*/
+
+//ldrFitTest();
+
+//ldr();
+//switchcover();
+//colon();
+//vtt9812fh();
+
+translate([-30,0,0]) colon();
+translate([-15,0,0]) colon();
+translate([0,0,0]) switchcover();
+if (revD) {
+    translate([15,0,0]) vtt9812fh();
+} else {
+    translate([15,0,0]) ldr();
+}
+
--- a/cad/hinge.mdr
+++ b/cad/hinge.mdr
--- a/cad/hinge.svg
+++ b/cad/hinge.svg
@@ -0,0 +1,65 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 -10 150 100" width="150mm" height="100mm" fill="none" stroke="#000" stroke-width="0.2">
+
+<!-- White 5mm Delrin -->
+<g>
+<rect x="45" y="39" width="3" height="5"/>
+<circle cx="50" cy="24.72" r="1.5"/>
+<circle cx="50" cy="36" r="1.5"/>
+<circle cx="50" cy="47.28" r="1.5"/>
+<polyline points="50,18.72 56,18.72 56,53.28 44,53.28 44,24.72"/>
+<path d="M44,24.72 A6 6 0 0 1 50,18.72"/>
+</g>
+
+<g>
+<rect x="32" y="39" width="3" height="5"/>
+<circle cx="30" cy="24.72" r="1.5"/>
+<circle cx="30" cy="36" r="1.5"/>
+<circle cx="30" cy="47.28" r="1.5"/>
+<polyline points="30,18.72 24,18.72 24,53.28 36,53.28 36,24.72"/>
+<path d="M30,18.72 A6 6 0 0 1 36,24.72"/>
+</g>
+
+<!-- Black 6mm Delrin -->
+<g>
+<circle cx="42" cy="5" r="1.5"/>
+<circle cx="30" cy="5" r="1.5"/>
+<path d="M30,11 L42,11 A6 6 0 0 0 42,-1 L30,-1 A6 6 0 0 0 30,11"/>
+</g>
+
+<g>
+<circle cx="10" cy="47.28" r="1.5"/>
+<circle cx="10" cy="36" r="1.5"/>
+<polyline points="16,53.28 4,53.28 4,30.72 16,30.72 16,53.28"/>
+</g>
+
+<!-- White 3mm Delrin -->
+<g>
+<circle cx="72" cy="5" r="1.3"/>
+<circle cx="60" cy="5" r="1.3"/>
+<path d="M60,11 L72,11 A6 6 0 0 0 72,-1 L 60,-1 A6 6 0 0 0 60,11"/>
+</g>
+
+
+<!-- Acetate film -->
+<g>
+<circle cx="122" cy="25" r="1.45"/>
+<circle cx="110" cy="25" r="1.45"/>
+<circle cx="122" cy="38" r="1.45"/>
+<circle cx="110" cy="38" r="1.45"/>
+<path d="M110,42 L 122,42
+A4 4 0 0 0 122,34
+L 121.5,34
+A2.5 2.5 0 0 1 121.5,29
+L 122,29
+A4 4 0 0 0 122,21
+L110,21
+A4 4 0 0 0 110,29
+L110.5,29
+A2.5 2.5 0 0 1 110.5,34
+L110,34
+A4 4 0 0 0 110,42
+"/>
+</g>
+
+</svg>
+
--- a/cad/main-3dprints-RevC/colons-revC.stl
+++ b/cad/main-3dprints-RevC/colons-revC.stl
--- a/cad/main-3dprints-RevC/ldr.stl
+++ b/cad/main-3dprints-RevC/ldr.stl
--- a/cad/main-3dprints-RevC/switchcover.stl
+++ b/cad/main-3dprints-RevC/switchcover.stl
--- a/cad/main-3dprints-RevD/Colons.step
+++ b/cad/main-3dprints-RevD/Colons.step
--- a/cad/main-3dprints-RevD/Phototransistor.step
+++ b/cad/main-3dprints-RevD/Phototransistor.step
--- a/cad/main-3dprints-RevD/Switchcover.step
+++ b/cad/main-3dprints-RevD/Switchcover.step
--- a/cad/main-3dprints-RevD/colons-revD.stl
+++ b/cad/main-3dprints-RevD/colons-revD.stl
--- a/cad/main-3dprints-RevD/phototransistor.stl
+++ b/cad/main-3dprints-RevD/phototransistor.stl
--- a/cad/main-3dprints-RevD/switchcover.stl
+++ b/cad/main-3dprints-RevD/switchcover.stl
--- a/cad/shelfstand/shelfstand-folded.FCStd
+++ b/cad/shelfstand/shelfstand-folded.FCStd
--- a/cad/shelfstand/shelfstand-folded.stl
+++ b/cad/shelfstand/shelfstand-folded.stl
--- a/cad/shelfstand/shelfstand-unfolded.FCStd
+++ b/cad/shelfstand/shelfstand-unfolded.FCStd
--- a/cad/shelfstand/shelfstand-unfolded.stl
+++ b/cad/shelfstand/shelfstand-unfolded.stl
--- a/cad/wallhanger/hingelock.FCStd
+++ b/cad/wallhanger/hingelock.FCStd
--- a/cad/wallhanger/hingelock.stl
+++ b/cad/wallhanger/hingelock.stl
--- a/cad/wallhanger/wallhanger-folded.FCStd
+++ b/cad/wallhanger/wallhanger-folded.FCStd
--- a/cad/wallhanger/wallhanger-folded.stl
+++ b/cad/wallhanger/wallhanger-folded.stl
--- a/cad/wallhanger/wallhanger-middle-unfolded.FCStd
+++ b/cad/wallhanger/wallhanger-middle-unfolded.FCStd
--- a/cad/wallhanger/wallhanger-middle-unfolded.stl
+++ b/cad/wallhanger/wallhanger-middle-unfolded.stl
--- a/cad/wallhanger/wallhanger-unfolded.FCStd
+++ b/cad/wallhanger/wallhanger-unfolded.FCStd
--- a/cad/wallhanger/wallhanger-unfolded.stl
+++ b/cad/wallhanger/wallhanger-unfolded.stl
--- a/mk4-bootloader/.cproject
+++ b/mk4-bootloader/.cproject
@@ -119,6 +119,7 @@
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.floatabi.628128892" name="Floating-point ABI" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.floatabi" useByScannerDiscovery="true" value="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.floatabi.value.hard" valueType="enumerated"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board.467584027" name="Board" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board" useByScannerDiscovery="false" value="genericBoard" valueType="string"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults.1800155271" name="Defaults" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults" useByScannerDiscovery="false" value="com.st.stm32cube.ide.common.services.build.inputs.revA.1.0.5 || Release || false || Executable || com.st.stm32cube.ide.mcu.gnu.managedbuild.toolchain.base.gnu-tools-for-stm32 || STM32L476RCTx || 0 || 0 || arm-none-eabi- || ${gnu_tools_for_stm32_compiler_path} || ../FATFS/App | ../USB_DEVICE/Target | ../Drivers/CMSIS/Include | ../Core/Inc | ../USB_DEVICE/App | ../Drivers/CMSIS/Device/ST/STM32L4xx/Include | ../FATFS/Target | ../Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Inc | ../Drivers/STM32L4xx_HAL_Driver/Inc | ../Middlewares/ST/STM32_USB_Device_Library/Core/Inc | ../Middlewares/Third_Party/FatFs/src | ../Drivers/STM32L4xx_HAL_Driver/Inc/Legacy ||  ||  || USE_HAL_DRIVER | STM32L476xx ||  || Drivers | Core/Startup | Middlewares | Core | FATFS | USB_DEVICE ||  ||  || ${workspace_loc:/${ProjName}/STM32L476RCTX_FLASH.ld} || true || NonSecure ||  || secure_nsclib.o ||  || None || " valueType="string"/>
+							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.convertbinary.1568961625" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.convertbinary" value="true" valueType="boolean"/>
 							<targetPlatform archList="all" binaryParser="org.eclipse.cdt.core.ELF" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform.699779650" isAbstract="false" osList="all" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform"/>
 							<builder buildPath="${workspace_loc:/mk4-bootloader}/Release" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder.1049602492" keepEnvironmentInBuildfile="false" managedBuildOn="true" name="Gnu Make Builder" parallelBuildOn="true" parallelizationNumber="optimal" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder"/>
 							<tool id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler.1341160678" name="MCU GCC Assembler" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler">
--- a/mk4-bootloader/.settings/language.settings.xml
+++ b/mk4-bootloader/.settings/language.settings.xml
@@ -6,7 +6,7 @@
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
 			<provider copy-of="extension" id="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser"/>
-			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="185955069870389989" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="0000000000000000000" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>
@@ -17,8 +17,7 @@
 			<provider copy-of="extension" id="org.eclipse.cdt.ui.UserLanguageSettingsProvider"/>
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
-			<provider copy-of="extension" id="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser"/>
-			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="115984574982993951" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="0000000000000000000" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>
--- a/mk4-bootloader/.settings/stm32cubeide.project.prefs
+++ b/mk4-bootloader/.settings/stm32cubeide.project.prefs
@@ -1,4 +1,4 @@
-2F62501ED4689FB349E356AB974DBE57=50C66168B03739D025B40EAABFA700A5
-8DF89ED150041C4CBC7CB9A9CAA90856=50C66168B03739D025B40EAABFA700A5
-DC22A860405A8BF2F2C095E5B6529F12=460787E75B2D603D0ACA93B88832D04C
+2F62501ED4689FB349E356AB974DBE57=5A72FCC93240365763D02B1C9D2B862E
+8DF89ED150041C4CBC7CB9A9CAA90856=5A72FCC93240365763D02B1C9D2B862E
+DC22A860405A8BF2F2C095E5B6529F12=264DA9245F9288E3067220E69F3ED6D7
 eclipse.preferences.version=1
--- a/mk4-bootloader/Core/Inc/main.h
+++ b/mk4-bootloader/Core/Inc/main.h
@@ -66,6 +66,7 @@ extern "C" {
 #define bSegDecode7 0b0000011100
 #define bSegDecode8 0b0111111100
 #define bSegDecode9 0b0110111100
+#define bSegDecodeU 0b0011111000

 #define bCat0 0b1111000000000000
 #define bCat1 0b1110001000000000
@@ -73,6 +74,30 @@ extern "C" {
 #define bCat3 0b1011001000000000
 #define bCat4 0b0111001000000000

+// Unable to mount / fatfs failure
+#define ERR_FATFS                 bSegDecode0
+
+// Firmware image on file system fails CRC check
+#define ERR_FS_IMG_CRC_INVALID    bSegDecode1
+
+// Loaded firmware image is invalid and no replacement found in file system
+#define ERR_INVALID_NO_FW         bSegDecode2
+
+// Flash page erase failed
+#define ERR_ERASE_FAILED          bSegDecode3
+
+// Data written to flash didn't match data read back
+#define ERR_WRITE_INVALID         bSegDecode4
+
+// Write data to flash returned failure
+#define ERR_WRITE_FAILED          bSegDecode5
+
+
+#define ERR_UNKNOWN               bSegDecode9
+
+// User request bootloader hang for backup USB stack
+#define ERR_USER                  bSegDecodeU
+
 /* USER CODE END EC */

 /* Exported macro ------------------------------------------------------------*/
@@ -82,6 +107,7 @@ extern "C" {

 /* Exported functions prototypes ---------------------------------------------*/
 void Error_Handler(void);
+void hang_error(uint16_t errno);

 /* USER CODE BEGIN EFP */

--- a/mk4-bootloader/Core/Src/main.c
+++ b/mk4-bootloader/Core/Src/main.c
@@ -71,27 +71,6 @@ static void MX_TIM4_Init(void);
 /* Private user code ---------------------------------------------------------*/
 /* USER CODE BEGIN 0 */

-// Firmware image on file system fails CRC check
-#define ERR_FS_IMG_CRC_INVALID    0b0011111100 // 0
-
-// Loaded firmware image is invalid and no replacement found in file system
-#define ERR_INVALID_NO_FW         0b0000011000 // 1
-
-// Flash page erase failed
-#define ERR_ERASE_FAILED          0b0101101100 // 2
-
-// Data written to flash didn't match data read back
-#define ERR_WRITE_INVALID         0b0100111100 // 3
-
-// Write data to flash returned failure
-#define ERR_WRITE_FAILED          0b0110011000 // 4
-
-//0b0110110100 // 5
-//0b0111110100 // 6
-//0b0000011100 // 7
-//0b0111111100 // 8
-//0b0110111100 // 9
-
 #define byteswap32(x) \
   ( ((x & 0xff000000) >> 24) | ((x & 0x00ff0000) >> 8) \
   | ((x & 0x0000ff00) <<  8) | ((x & 0x000000ff) << 24))
@@ -124,7 +103,7 @@ void setDisplayPWM(uint32_t bright){
  HAL_DMA_Start(&hdma_tim4_up, (uint32_t)buffer_c, (uint32_t)&GPIOC->ODR, bright);
 }

-uint8_t ejected_state = 0;
+volatile uint8_t ejected_state = 0;

 void hang_error(uint16_t errno){
  MX_USB_DEVICE_Init();
@@ -207,8 +186,7 @@ uint32_t app_crc()
  return result;
 }

-
-void launch_app(){
+void __attribute__((naked,noreturn)) launch_app(){
  HAL_RCC_DeInit();
  HAL_DeInit();

@@ -225,6 +203,7 @@ void launch_app(){

  __set_MSP(_app_start[0]);
  ((void (*)(void)) _app_start[1])();
+  __builtin_unreachable();
 }


@@ -404,7 +383,7 @@ int main(void)
  __HAL_TIM_ENABLE(&htim4);

  _Bool new_fw_present;
-  uint32_t new_fw_crc;
+  uint32_t new_fw_crc =0;

  // Calculate CRC of loaded image
  uint32_t loaded_fw_crc = app_crc();
@@ -423,6 +402,11 @@ int main(void)
 // debug force reload
 // new_fw_crc=0;

+  // Hinge TX connection shorted to ground - force bootloader to hang
+  if ((GPIOA->IDR & (1<<2))==0) {
+    hang_error(ERR_USER);
+  }
+

  if (loaded_fw_crc == byteswap32(*(uint32_t*)(FLASH_BASE + BOOT_SIZE + APP_SIZE -4)) ) { // loaded firmware valid

@@ -728,6 +712,25 @@ static void MX_GPIO_Init(void)
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();

+  /*Configure GPIO pin Output Level */
+  HAL_GPIO_WritePin(GPIOA, GPIO_PIN_0|GPIO_PIN_1, GPIO_PIN_SET);
+
+  /*Configure GPIO pin : PA0 PA1 */
+  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1;
+  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
+  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
+
+  /**USART2 GPIO Configuration
+  PA2     ------> USART2_TX
+  PA3     ------> USART2_RX
+  */
+  GPIO_InitStruct.Pin = GPIO_PIN_2;
+  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
+  GPIO_InitStruct.Pull = GPIO_PULLUP;
+  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
+
  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_13|GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_2
                          |GPIO_PIN_3|GPIO_PIN_4|GPIO_PIN_5|GPIO_PIN_6
@@ -777,7 +780,7 @@ void Error_Handler(void)
 {
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
-  while(1){}
+  hang_error(ERR_UNKNOWN);
  /* USER CODE END Error_Handler_Debug */
 }

--- a/mk4-bootloader/Core/Src/sysmem.c
+++ b/mk4-bootloader/Core/Src/sysmem.c
@@ -24,6 +24,7 @@
 /* Includes */
 #include <errno.h>
 #include <stdio.h>
+#include <sys/types.h>

 /* Variables */
 extern int errno;
--- a/mk4-bootloader/Core/Src/version.c
+++ b/mk4-bootloader/Core/Src/version.c
@@ -1,4 +1,4 @@
 // in pre-build steps: rm -f Core/Src/version.o

-#define VERSION_STRING "BootVer 0.0.1 "
+#define VERSION_STRING "BootVer 0.0.3 "
 #include "../../../version.h"
--- a/mk4-bootloader/FATFS/App/fatfs.c
+++ b/mk4-bootloader/FATFS/App/fatfs.c
@@ -34,8 +34,10 @@ void MX_FATFS_Init(void)

  /* USER CODE BEGIN Init */

+  // This should never fail, as f_mount does not do anything until
+  // the first read (unless forced)
  if (f_mount(&USERFatFS, (TCHAR const*)USERPath, 0) != FR_OK)
-    Error_Handler();
+    hang_error(ERR_FATFS);

  /* USER CODE END Init */
 }
--- a/mk4-bootloader/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c
+++ b/mk4-bootloader/Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c
@@ -114,7 +114,7 @@ static int8_t SCSI_ProcessWrite(USBD_HandleTypeDef *pdev, uint8_t lun);
 */
 int8_t SCSI_ProcessCmd(USBD_HandleTypeDef *pdev, uint8_t lun, uint8_t *cmd)
 {
-  extern uint8_t ejected_state;
+  extern volatile uint8_t ejected_state;
  if (ejected_state==1) ejected_state=2;
  switch (cmd[0])
  {
--- a/mk4-bootloader/STM32L476RCTX_FLASH.ld
+++ b/mk4-bootloader/STM32L476RCTX_FLASH.ld
@@ -145,7 +145,11 @@ SECTIONS
    
  } >RAM AT> FLASH

-  .pad : { KEEP(*(.pad)) } > PAD
+  .pad :
+  {
+    KEEP(*(.pad))
+    . = LENGTH(PAD);
+  } > PAD

  /* Uninitialized data section into "RAM" Ram type memory */
  . = ALIGN(4);
--- a/mk4-date/.cproject
+++ b/mk4-date/.cproject
@@ -115,6 +115,7 @@
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_coreid.914925487" name="Core" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_coreid" useByScannerDiscovery="false" value="0" valueType="string"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board.2071828213" name="Board" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board" useByScannerDiscovery="false" value="genericBoard" valueType="string"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults.974500262" name="Defaults" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults" useByScannerDiscovery="false" value="com.st.stm32cube.ide.common.services.build.inputs.revA.1.0.5 || Release || false || Executable || com.st.stm32cube.ide.mcu.gnu.managedbuild.toolchain.base.gnu-tools-for-stm32 || STM32L010C6Tx || 0 || 0 || arm-none-eabi- || ${gnu_tools_for_stm32_compiler_path} || ../Drivers/CMSIS/Include | ../Core/Inc | ../Drivers/STM32L0xx_HAL_Driver/Inc | ../Drivers/CMSIS/Device/ST/STM32L0xx/Include ||  ||  || HSE_VALUE=8000000 | HSE_STARTUP_TIMEOUT=100 | HSI_VALUE=16000000 | LSE_STARTUP_TIMEOUT=5000 | LSE_VALUE=32768 | DATA_CACHE_ENABLE=1 | LSI_VALUE=37000 | MSI_VALUE=2097000 | VDD_VALUE=3300 | INSTRUCTION_CACHE_ENABLE=1 | USE_FULL_LL_DRIVER | STM32L010x6 | PREFETCH_ENABLE=0 ||  || Drivers | Core/Startup | Core ||  ||  || ${workspace_loc:/${ProjName}/STM32L010C6TX_FLASH.ld} || true || NonSecure ||  || secure_nsclib.o ||  || None || " valueType="string"/>
+							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.convertbinary.572415805" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.convertbinary" value="true" valueType="boolean"/>
 							<targetPlatform archList="all" binaryParser="org.eclipse.cdt.core.ELF" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform.131568553" isAbstract="false" osList="all" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform"/>
 							<builder buildPath="${workspace_loc:/mk4-date}/Release" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder.744708051" keepEnvironmentInBuildfile="false" managedBuildOn="true" name="Gnu Make Builder" parallelBuildOn="true" parallelizationNumber="optimal" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder"/>
 							<tool id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler.2032152780" name="MCU GCC Assembler" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler">
--- a/mk4-date/.settings/language.settings.xml
+++ b/mk4-date/.settings/language.settings.xml
@@ -6,7 +6,7 @@
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
 			<provider copy-of="extension" id="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser"/>
-			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="179684480100589093" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="0000000000000000000" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>
@@ -17,8 +17,7 @@
 			<provider copy-of="extension" id="org.eclipse.cdt.ui.UserLanguageSettingsProvider"/>
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
-			<provider copy-of="extension" id="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser"/>
-			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="179684480100589093" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="0000000000000000000" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>
--- a/mk4-date/Core/Src/sysmem.c
+++ b/mk4-date/Core/Src/sysmem.c
@@ -24,6 +24,7 @@
 /* Includes */
 #include <errno.h>
 #include <stdio.h>
+#include <sys/types.h>

 /* Variables */
 extern int errno;
--- a/mk4-time/.cproject
+++ b/mk4-time/.cproject
@@ -124,6 +124,7 @@
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board.283690338" name="Board" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.target_board" useByScannerDiscovery="false" value="genericBoard" valueType="string"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults.950842211" name="Defaults" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.defaults" useByScannerDiscovery="false" value="com.st.stm32cube.ide.common.services.build.inputs.revA.1.0.5 || Release || false || Executable || com.st.stm32cube.ide.mcu.gnu.managedbuild.toolchain.base.gnu-tools-for-stm32 || STM32L476RGTx || 0 || 0 || arm-none-eabi- || ${gnu_tools_for_stm32_compiler_path} || ../FATFS/App | ../USB_DEVICE/Target | ../Drivers/CMSIS/Include | ../Core/Inc | ../USB_DEVICE/App | ../Drivers/CMSIS/Device/ST/STM32L4xx/Include | ../FATFS/Target | ../Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Inc | ../Drivers/STM32L4xx_HAL_Driver/Inc | ../Middlewares/ST/STM32_USB_Device_Library/Core/Inc | ../Middlewares/Third_Party/FatFs/src | ../Drivers/STM32L4xx_HAL_Driver/Inc/Legacy ||  ||  || USE_HAL_DRIVER | STM32L476xx | USE_FULL_LL_DRIVER ||  || Drivers | Core/Startup | Middlewares | Core | FATFS | USB_DEVICE ||  ||  || ${workspace_loc:/${ProjName}/STM32L476RGTX_FLASH.ld} || true || NonSecure ||  || secure_nsclib.o ||  || None || " valueType="string"/>
 							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.nanoprintffloat.34089756" name="Use float with printf from newlib-nano (-u _printf_float)" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.nanoprintffloat" useByScannerDiscovery="false" value="true" valueType="boolean"/>
+							<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.convertbinary.343825891" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.option.convertbinary" value="true" valueType="boolean"/>
 							<targetPlatform archList="all" binaryParser="org.eclipse.cdt.core.ELF" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform.620354801" isAbstract="false" osList="all" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.targetplatform"/>
 							<builder buildPath="${workspace_loc:/mk4-time}/Release" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder.1346654687" keepEnvironmentInBuildfile="false" managedBuildOn="true" name="Gnu Make Builder" parallelBuildOn="true" parallelizationNumber="optimal" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.builder"/>
 							<tool id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler.110828471" name="MCU GCC Assembler" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.assembler">
--- a/mk4-time/.settings/language.settings.xml
+++ b/mk4-time/.settings/language.settings.xml
@@ -5,8 +5,7 @@
 			<provider copy-of="extension" id="org.eclipse.cdt.ui.UserLanguageSettingsProvider"/>
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
-			<provider copy-of="extension" id="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser"/>
-			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="185955069870389989" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="0000000000000000000" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>
@@ -17,8 +16,7 @@
 			<provider copy-of="extension" id="org.eclipse.cdt.ui.UserLanguageSettingsProvider"/>
 			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
 			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
-			<provider copy-of="extension" id="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser"/>
-			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="115984574982993951" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
+			<provider class="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" console="false" env-hash="0000000000000000000" id="com.st.stm32cube.ide.mcu.toolchain.armnone.setup.CrossBuiltinSpecsDetector" keep-relative-paths="false" name="MCU ARM GCC Built-in Compiler Settings" parameter="${COMMAND} ${FLAGS} -E -P -v -dD &quot;${INPUTS}&quot;" prefer-non-shared="true">
 				<language-scope id="org.eclipse.cdt.core.gcc"/>
 				<language-scope id="org.eclipse.cdt.core.g++"/>
 			</provider>
--- a/mk4-time/.settings/stm32cubeide.project.prefs
+++ b/mk4-time/.settings/stm32cubeide.project.prefs
@@ -1,4 +1,4 @@
 2F62501ED4689FB349E356AB974DBE57=567EE81E60C8A1A45682D5C5317E6662
 8DF89ED150041C4CBC7CB9A9CAA90856=567EE81E60C8A1A45682D5C5317E6662
-DC22A860405A8BF2F2C095E5B6529F12=AA705B8CAFB58EBE5E4C71DC01DEB86F
+DC22A860405A8BF2F2C095E5B6529F12=AFF9D44B33335AD8FB5822992DE506A7
 eclipse.preferences.version=1
--- a/mk4-time/Core/Inc/main.h
+++ b/mk4-time/Core/Inc/main.h
@@ -77,6 +77,9 @@ extern uint16_t buffer_b[];
 extern _Bool delayedReadConfigFile;
 extern _Bool delayedCheckOnEject;

+extern _Bool waitingForLatch;
+extern _Bool resendDate;
+
 /* USER CODE END ET */

 /* Exported constants --------------------------------------------------------*/
@@ -148,6 +151,7 @@ enum {
  MODE_TEXT,
  MODE_FIRMWARE_CRC_T,
  MODE_FIRMWARE_CRC_D,
+  MODE_VBAT,

  NUM_DISPLAY_MODES
 };
@@ -182,6 +186,18 @@ enum {
  RULES_CATEGORY_UNKNOWN,
  RULES_ZONE_UNKNOWN
 };
+
+enum {
+  SV_GPS_L1=0,
+  SV_GPS_UNKNOWN,
+  SV_GLONASS_L1,
+  SV_GLONASS_UNKNOWN,
+  SV_GALILEO_E1,
+  SV_GALILEO_UNKNOWN,
+  SV_BEIDOU_B1,
+  SV_BEIDOU_UNKNOWN,
+  SV_COUNT
+};
 /* USER CODE END EC */

 /* Exported macro ------------------------------------------------------------*/
@@ -200,7 +216,7 @@ void Error_Handler(void);

 /* USER CODE BEGIN EFP */
 void decodeRMC(void);
-void decodeGSV(void);
+void decodeGSV(uint8_t rec);
 void setDisplayPWM(uint32_t bright);
 void write_rtc(void);
 void displayOff(void);
@@ -226,9 +242,13 @@ void monitor_vbus(void);
 #define triggerPendSV() \
  SCB->ICSR = SCB_ICSR_PENDSVSET_Msk;

+#define sendLatch() \
+  huart2.Instance->TDR = 0xFE;
+
 #define loadNextTimestamp() \
  latchSegments() \
-  huart2.Instance->TDR = 0xFE; \
+  sendLatch() \
+  waitingForLatch=0;\
  triggerPendSV()

 extern uint32_t __VECTORS_FLASH[];
--- a/mk4-time/Core/Inc/qspi_drv.h
+++ b/mk4-time/Core/Inc/qspi_drv.h
@@ -61,6 +61,6 @@ QSPI_STATUS QSPI_Write_Sector(uint8_t *pData, uint32_t address);
 uint8_t QSPI_Initialized();
 uint8_t QSPI_Locked();

-extern uint32_t qspi_write_time;
-extern uint32_t qspi_usb_read_time;
+extern volatile uint32_t qspi_write_time;
+extern volatile uint32_t qspi_usb_read_time;
 #endif
--- a/mk4-time/Core/Src/chainloader.c
+++ b/mk4-time/Core/Src/chainloader.c
@@ -367,15 +367,21 @@ void firmwareCheckOnEject(){
  if (f_open(&file2, "/FWT.BIN", FA_READ) == FR_OK) {
    f_lseek(&file2, TIME_APP_SIZE - 4);
    f_read(&file2, &new_fwt_crc, 4, &rc);
-    if (rc==4 && new_fwt_crc != cur_fwt_crc)
+    if (rc==4 && new_fwt_crc != cur_fwt_crc) {
+      displayOff();
+      HAL_Delay(5);
      NVIC_SystemReset();
+    }
  }

  if (f_open(&file1, "/FWD.BIN", FA_READ) == FR_OK) {
    f_lseek(&file1, DATE_APP_SIZE - 4);
    f_read(&file1, &new_fwd_crc, 4, &rc);
-    if (rc==4 && new_fwd_crc != cur_fwd_crc)
+    if (rc==4 && new_fwd_crc != cur_fwd_crc) {
+      displayOff();
+      HAL_Delay(5);
      NVIC_SystemReset();
+    }
  }
  delayedCheckOnEject = 0;
 }
--- a/mk4-time/Core/Src/main.c
+++ b/mk4-time/Core/Src/main.c
@@ -50,6 +50,7 @@

 /* Private variables ---------------------------------------------------------*/
 ADC_HandleTypeDef hadc1;
+ADC_HandleTypeDef hadc3;

 CRC_HandleTypeDef hcrc;

@@ -96,6 +97,7 @@ static void MX_TIM7_Init(void);
 static void MX_CRC_Init(void);
 static void MX_LPTIM1_Init(void);
 static void MX_TIM5_Init(void);
+static void MX_ADC3_Init(void);
 /* USER CODE BEGIN PFP */
 void tmToBcd(struct tm *in, bcdStamp_t *out );
 uint8_t loadRulesSingle(char * str);
@@ -118,12 +120,14 @@ uint8_t uart2_tx_buffer[32];
 volatile uint16_t buffer_adc[ADC_BUFFER_SIZE] = {0};
 uint16_t buffer_dac[DAC_BUFFER_SIZE] = {[0 ... DAC_BUFFER_SIZE-1] = 4095};
 float dac_target=4095;
+float vbat = 0.0;

 uint16_t buffer_colons_L[200] = {0};
 uint16_t buffer_colons_R[200] = {0};

 uint8_t nmea[NMEA_BUF_SIZE];
-uint8_t GPS_sv = 255, GLONASS_sv = 255;
+uint8_t satview[SV_COUNT];
+uint8_t satview_stale = 0;

 time_t currentTime;
 bcdStamp_t nextBcd;
@@ -160,6 +164,10 @@ char textDisplay[32];
 _Bool delayedLoadRules = 0;
 _Bool delayedReadConfigFile = 0;
 _Bool delayedCheckOnEject = 0;
+uint32_t delayedDisplayFreq = 0;
+
+_Bool waitingForLatch = 0;
+_Bool resendDate = 0;

 uint32_t LPTIM1_high;

@@ -206,8 +214,21 @@ void memcpyword(volatile uint32_t *dest, volatile uint32_t *src, size_t n){
  }
 }

+// 12 bytes at 115200 8E1 is 1.14ms, 32 bytes would be 3.06ms
 void sendDate( _Bool now ){
+  if (waitingForLatch) {
+    if (countMode==COUNT_HIDDEN) {
+      // if we've entered count_hidden while waiting for latch, it will never happen
+      sendLatch()
+      waitingForLatch=0;
+    } else {
+      resendDate=1;
+      return;
+    }
+  }
+
  uint8_t i = 10;
+  HAL_UART_AbortTransmit(&huart2);
  uart2_tx_buffer[0] = CMD_LOAD_TEXT;

  switch (displayMode) {
@@ -302,12 +323,28 @@ void sendDate( _Bool now ){
    i = sprintf((char*)&uart2_tx_buffer[1], "%s", wday_str[tm_wday]);
    break;
  case MODE_SATVIEW:
-    if (GPS_sv==255) {
-      i = sprintf((char*)&uart2_tx_buffer[1], "GPS - L-");
-    } else if (GLONASS_sv==255) {
-      i = sprintf((char*)&uart2_tx_buffer[1], "GPS %d. L-", GPS_sv);
+    if (satview[SV_GPS_L1]==255 && satview[SV_GPS_UNKNOWN]==255) {
+      i = sprintf((char*)&uart2_tx_buffer[1], "GPS -");
    } else {
-      i = sprintf((char*)&uart2_tx_buffer[1], "GPS %d. L%d", GPS_sv, GLONASS_sv);
+      uint8_t GPS_sv = 0, GLONASS_sv = 0, GALILEO_sv = 0, BEIDOU_sv = 0;
+      if (satview[SV_GPS_L1]!=255) GPS_sv += satview[SV_GPS_L1];
+      if (satview[SV_GPS_UNKNOWN]!=255) GPS_sv += satview[SV_GPS_UNKNOWN];
+      if (satview[SV_GLONASS_L1]!=255) GLONASS_sv += satview[SV_GLONASS_L1];
+      if (satview[SV_GLONASS_UNKNOWN]!=255) GLONASS_sv += satview[SV_GLONASS_UNKNOWN];
+      if (satview[SV_GALILEO_E1]!=255) GALILEO_sv += satview[SV_GALILEO_E1];
+      if (satview[SV_GALILEO_UNKNOWN]!=255) GALILEO_sv += satview[SV_GALILEO_UNKNOWN];
+      if (satview[SV_BEIDOU_B1]!=255) BEIDOU_sv += satview[SV_BEIDOU_B1];
+      if (satview[SV_BEIDOU_UNKNOWN]!=255)  BEIDOU_sv += satview[SV_BEIDOU_UNKNOWN];
+
+      if (GLONASS_sv>0 && GLONASS_sv>=GALILEO_sv && GLONASS_sv>=BEIDOU_sv) {
+        i = sprintf((char*)&uart2_tx_buffer[1], "GPS %d L%d", GPS_sv, GLONASS_sv);
+      } else if (GALILEO_sv>0 && GALILEO_sv>=GLONASS_sv && GALILEO_sv>=BEIDOU_sv){
+        i = sprintf((char*)&uart2_tx_buffer[1], "GPS %d A%d", GPS_sv, GALILEO_sv);
+      } else if (BEIDOU_sv>0 && BEIDOU_sv>=GLONASS_sv && BEIDOU_sv>=GALILEO_sv){
+        i = sprintf((char*)&uart2_tx_buffer[1], "GPS %d b%d", GPS_sv, BEIDOU_sv);
+      } else {
+        i = sprintf((char*)&uart2_tx_buffer[1], "GPS %d -", GPS_sv);
+      }
    }
    break;
  case MODE_STANDBY:
@@ -329,6 +366,13 @@ void sendDate( _Bool now ){
      i=1;
    }
    break;
+  case MODE_VBAT:
+    if (vbat == 0.0) {
+      i = sprintf((char*)&uart2_tx_buffer[1], "bat -");
+    } else {
+      i = sprintf((char*)&uart2_tx_buffer[1], "bat %.4f", vbat);
+    }
+    break;
  case MODE_FIRMWARE_CRC_T:
  {
    extern uint32_t _app_crc[];
@@ -340,8 +384,12 @@ void sendDate( _Bool now ){
    uart2_tx_buffer[0]=CMD_SHOW_CRC;
    break;
  }
-  uart2_tx_buffer[++i]= now ? CMD_RELOAD_TEXT : '\n';
-  HAL_UART_AbortTransmit(&huart2);
+  if (now) {
+    uart2_tx_buffer[++i]= CMD_RELOAD_TEXT;
+  } else {
+    uart2_tx_buffer[++i]= '\n';
+    waitingForLatch=1;
+  }
  HAL_UART_Transmit_DMA(&huart2, uart2_tx_buffer, i+1);

 }
@@ -580,12 +628,47 @@ void decodeRMC(void){

 }

-void decodeGSV(void){
-  uint8_t sv = (nmea[11]-'0')*10 + (nmea[12]-'0');
-  if (nmea[2] == 'P') {
-      GPS_sv = sv;
-  } else if (nmea[2] == 'L') {
-      GLONASS_sv = sv;
+void decodeGSV(uint8_t rec){
+  unsigned int sv = (nmea[11]-'0')*10 + (nmea[12]-'0');
+  uint8_t constellation = nmea[2];
+  uint8_t signal_id;
+
+  // signal ID is not always present in GSV (on M8Q)
+
+  unsigned int num_fields = 0, r=0;
+  while (++r<rec) if (nmea[r]==',') num_fields++;
+
+  if (num_fields % 4 != 0) {
+    signal_id = '0';
+  } else {
+    signal_id = nmea[rec-6];
+  }
+
+  if (constellation == 'P') {
+      if (signal_id == '0') {
+        satview[SV_GPS_UNKNOWN] = sv;
+      } else {
+        satview[SV_GPS_L1] = sv;
+      }
+      satview_stale = 0;
+  } else if (constellation == 'L') {
+    if (signal_id == '0') {
+      satview[SV_GLONASS_UNKNOWN] = sv;
+    } else {
+      satview[SV_GLONASS_L1] = sv;
+    }
+  } else if (constellation == 'A') {
+    if (signal_id == '0') {
+      satview[SV_GALILEO_UNKNOWN] = sv;
+    } else {
+      satview[SV_GALILEO_E1] = sv;
+    }
+  } else if (constellation == 'B') {
+    if (signal_id == '0') {
+      satview[SV_BEIDOU_UNKNOWN] = sv;
+    } else {
+      satview[SV_BEIDOU_B1] = sv;
+    }
  }
 }

@@ -619,14 +702,21 @@ void displayOn(void){
 }

 void setDisplayFreq(uint32_t freq){
+  if (waitingForLatch) {
+    delayedDisplayFreq = freq;
+    return;
+  }

-  if (freq<1000 || freq>100000) return;
+  if (freq<1000 || freq>100000) {delayedDisplayFreq=0; return;}

-  uart2_tx_buffer[0]= CMD_SET_FREQUENCY;
-  uart2_tx_buffer[1]= (freq>>14) & 0x7F;
-  uart2_tx_buffer[2]= (freq>>7)  & 0x7F;
-  uart2_tx_buffer[3]= (freq)     & 0x7F;
-  HAL_UART_Transmit(&huart2, uart2_tx_buffer, 4, 2);
+  uint8_t tx_buf[4];
+  tx_buf[0]= CMD_SET_FREQUENCY;
+  tx_buf[1]= (freq>>14) & 0x7F;
+  tx_buf[2]= (freq>>7)  & 0x7F;
+  tx_buf[3]= (freq)     & 0x7F;
+  if (HAL_UART_Transmit(&huart2, tx_buf, 4, 2) == HAL_OK) {
+    delayedDisplayFreq = 0;
+  }

  uint32_t arr = round(16000000.0 / (float)freq) -1.0;

@@ -742,11 +832,10 @@ void parseConfigString(char *key, char *value) {

  if (strcasecmp(key, "text") == 0) {

-     strcpy(textDisplay, value);
+    strcpy(textDisplay, value);

  } else if (strcasecmp(key, "MATRIX_FREQUENCY") == 0) {

-    //todo: check not waiting for latch
    setDisplayFreq(atoi(value));

  } else if (strcasecmp(key, "zone_override") == 0) {
@@ -804,6 +893,8 @@ void parseConfigString(char *key, char *value) {
    set_mode_enabled(MODE_DEBUG_RTC, value);
  } else if (strcasecmp(key, "MODE_TEXT") == 0) {
    set_mode_enabled(MODE_TEXT, value);
+  } else if (strcasecmp(key, "MODE_VBAT") == 0) {
+    set_mode_enabled(MODE_VBAT, value);
  } else if (strcasecmp(key, "MODE_FIRMWARE_CRC") == 0) {
    set_mode_enabled(MODE_FIRMWARE_CRC_D, value);
    set_mode_enabled(MODE_FIRMWARE_CRC_T, value);
@@ -1340,7 +1431,15 @@ void monitor_vbus(void){
  vbus_state = vbus;
 }

-
+void measure_vbat(void){
+  ADC123_COMMON->CCR |= ADC_CCR_VBATEN;
+  HAL_Delay(5);
+  HAL_ADC_Start(&hadc3);
+  HAL_ADC_PollForConversion(&hadc3, 10);
+  uint16_t adc = HAL_ADC_GetValue(&hadc3);
+  ADC123_COMMON->CCR &= ~ADC_CCR_VBATEN;
+  vbat = (float)adc *0.0024102564102564104;//3*3.29/4095.0;
+}

 uint8_t f_getzcmp(FIL* fp, char * str){
  unsigned int rc;
@@ -1475,7 +1574,7 @@ void setPrecision(void){
      SetSysTick( &SysTick_CountUp_P0 );
    }

-  } else if (countMode == COUNT_DOWN) {
+  } else if (displayMode == MODE_COUNTDOWN) {

    if (config.countdown_to >= currentTime) {
      SetPPS( &PPS_Countdown );
@@ -1501,6 +1600,7 @@ void setPrecision(void){
      }

    } else {
+      countMode = COUNT_HIDDEN;
      SetSysTick( &SysTick_CountUp_NoUpdate );
      SetPPS( &PPS_NoUpdate );
      buffer_c[0].low=cSegDecode0;
@@ -1519,10 +1619,10 @@ void setPrecision(void){
  }
 }

+#define justExited(x) ((oldMode==x) && (displayMode != x))
 void nextMode(_Bool reverse){

-  _Bool wasOff = (displayMode==MODE_STANDBY);
-  _Bool wasCountdown = (displayMode==MODE_COUNTDOWN);
+  uint8_t oldMode = displayMode;

  if (requestMode!=255){
    if (!config.modes_enabled[requestMode]) {
@@ -1541,36 +1641,35 @@ void nextMode(_Bool reverse){
    } while (!config.modes_enabled[displayMode]);
  }

-  if (wasOff && displayMode != MODE_STANDBY) displayOn();
-  if ( displayMode == MODE_ISO_WEEK ||
-       (wasCountdown && displayMode != MODE_COUNTDOWN)) {
-    // It shouldn't be possible to exit countdown mode at .9 seconds
-    // but if we did, it would show the wrong time for .1 seconds
+  if (justExited(MODE_VBAT)) vbat = 0.0;
+  if (justExited(MODE_STANDBY)) displayOn();
+  if ( displayMode == MODE_ISO_WEEK || justExited(MODE_COUNTDOWN)) {
+    // If we exit countdown mode at .9 seconds
+    // it will show the wrong time for .1 seconds
    setNextTimestamp(currentTime);
  }

  if (displayMode == MODE_SHOW_OFFSET) {
-    if (countMode != COUNT_HIDDEN) {
-      countMode = COUNT_HIDDEN;
-      SetSysTick( &SysTick_CountUp_NoUpdate );
-      SetPPS( &PPS_NoUpdate );
-      colonAnimationStop()
-      TIM2->CCR1 = 0; // specific to show_offset
-      TIM2->CCR2 = 300;
-    }
+    countMode = COUNT_HIDDEN;
+    SetSysTick( &SysTick_CountUp_NoUpdate );
+    SetPPS( &PPS_NoUpdate );
+    colonAnimationStop()
+    TIM2->CCR1 = 0; // specific to show_offset
+    TIM2->CCR2 = 300;
  } else if (displayMode == MODE_COUNTDOWN) {
-    if (countMode != COUNT_DOWN) {
+
+    if (config.countdown_to >= currentTime) {
      countMode = COUNT_DOWN;
-
-      if (config.countdown_to >= currentTime) {
-        setNextCountdown(currentTime);
-      } else countdown_days = 0;
-
-      setPrecision();
-      TIM2->CCR1 = 0;
-      TIM2->CCR2 = 0;
-      latchSegments();
+      setNextCountdown(currentTime);
+    } else {
+      countMode = COUNT_HIDDEN;
+      countdown_days = 0;
    }
+    setPrecision();
+    TIM2->CCR1 = 0;
+    TIM2->CCR2 = 0;
+    latchSegments();
+
  }
  else {
    if (countMode != COUNT_NORMAL) {
@@ -1582,27 +1681,13 @@ void nextMode(_Bool reverse){
      latchSegments();
    }
  }
-
+  sendDate(1);
 }
 void button1pressed(void){
-
-  // 12 bytes at 115200 8E1 is 1.14ms
-
  nextMode(0);
-
-  // Normally this routine is only called when it is safe to do so
-  // But if we have just left COUNT_HIDDEN, the button press could have been called at any time, so
-  // avoid transmission if <3ms till rollover.
-  // If we are still in COUNT_HIDDEN, always send.
-  if (countMode == COUNT_HIDDEN || decisec!=9 || centisec!=9 || millisec<7)
-    sendDate(1);
-  // todo: detect this and resend date in pendsv
-
 }
 void button2pressed(void){
  nextMode(1);
-  if (countMode == COUNT_HIDDEN || decisec!=9 || centisec!=9 || millisec<7)
-    sendDate(1);
 }

 void generateDACbuffer(uint16_t * buf) {
@@ -1740,7 +1825,7 @@ int main(void)
  USART1->CR1 |= USART_CR1_UE;


-
+  MX_ADC3_Init();

  // Configure ADC and DAC DMA for display brightness
  HAL_ADC_Start(&hadc1);
@@ -1785,6 +1870,8 @@ int main(void)
  readConfigFile();
  checkDelayedLoadRules();

+  measure_vbat();
+
  if (RTC->ISR & RTC_ISR_INITS) //RTC contains non-zero data
  {
    RTC_DateTypeDef sdate;
@@ -1795,7 +1882,7 @@ int main(void)
      memcpyword( (uint32_t*)zone,  (uint32_t*)&(RTC->BKP0R), 8 );
      zone[31]=0;

-      if (loadRulesSingle(zone) != RULES_OK){ // takes 34ms -O0, 26ms -O2
+      if (loadRulesSingle(zone) != RULES_OK){ // takes ~8ms
        memcpyword( (uint32_t*)loadedRulesString,  (uint32_t*)&(RTC->BKP0R), 8 );
        loadedRulesString[31]=0;//paranoia
        memcpyword( (uint32_t*)rules, (uint32_t*)&(RTC->BKP8R), 22 );
@@ -1832,7 +1919,17 @@ int main(void)
    setNextTimestamp( currentTime );
    sendDate(1);
    latchSegments();
-    rtc_good=1;
+
+    // As the coin cell goes flat, the RTC stops ticking long before the backup registers die.
+    // Powering on with a flat battery means the clock thinks no time has passed, and assumes it has good precision.
+    // Explicitly stop this by checking the battery voltage.
+    if (vbat > 2.70) {
+      rtc_good=1;
+    } else {
+      // trash the calibration time to ensure lowest precision display
+      if (currentTime - rtc_last_calibration < config.tolerance_100ms)
+        rtc_last_calibration -= config.tolerance_100ms +1;
+    }

  } else { // backup domain reset

@@ -1842,11 +1939,13 @@ int main(void)
    MX_RTC_Init();
  }

+  vbat = 0.0; // don't allow measurement to go stale
+
  setPrecision();
  PPS_Init();
  HAL_UART_Receive_DMA(&huart1, nmea, sizeof(nmea));

-
+//#define MEASURE_LOOKUP_TIME

  /* USER CODE END 2 */

@@ -1861,14 +1960,26 @@ int main(void)
      new_position=0;
      FIL mapfile;
      if (f_open(&mapfile, MAP_FILENAME, FA_READ) == FR_OK) {
+#ifdef MEASURE_LOOKUP_TIME
+        uint32_t start=uwTick;
+#endif
        ZoneDetect *const zdb = ZDOpenDatabase(&mapfile);

        if (!zdb) {
          // mapfile error
        } else {
          char* zone = ZDHelperSimpleLookupString(zdb, latitude, longitude);
+#ifdef MEASURE_LOOKUP_TIME
+          uint32_t ztime=uwTick-start;
+#endif
          if (zone && !delayedLoadRules) {
+#ifdef MEASURE_LOOKUP_TIME
+            start=uwTick;
+#endif
            loadRulesSingle(zone);
+#ifdef MEASURE_LOOKUP_TIME
+            sprintf(textDisplay,"d%ld L%ld",ztime, uwTick-start);
+#endif
          }
          free(zone);
          ZDCloseDatabase(zdb);
@@ -1888,9 +1999,13 @@ int main(void)

    checkDelayedLoadRules();

+    if (delayedDisplayFreq) setDisplayFreq(delayedDisplayFreq);
+
    monitor_vbus();

-    // qspi_usb_read_time too?
+    if (displayMode == MODE_VBAT)
+      measure_vbat();
+

    /* USER CODE END WHILE */

@@ -2035,6 +2150,72 @@ static void MX_ADC1_Init(void)

 }

+/**
+  * @brief ADC3 Initialization Function
+  * @param None
+  * @retval None
+  */
+static void MX_ADC3_Init(void)
+{
+
+  /* USER CODE BEGIN ADC3_Init 0 */
+
+  /* USER CODE END ADC3_Init 0 */
+
+  ADC_ChannelConfTypeDef sConfig = {0};
+
+  /* USER CODE BEGIN ADC3_Init 1 */
+
+
+  /* USER CODE END ADC3_Init 1 */
+  /** Common config
+  */
+  hadc3.Instance = ADC3;
+  hadc3.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV2;
+  hadc3.Init.Resolution = ADC_RESOLUTION_12B;
+  hadc3.Init.DataAlign = ADC_DATAALIGN_RIGHT;
+  hadc3.Init.ScanConvMode = ADC_SCAN_DISABLE;
+  hadc3.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
+  hadc3.Init.LowPowerAutoWait = DISABLE;
+  hadc3.Init.ContinuousConvMode = DISABLE;
+  hadc3.Init.NbrOfConversion = 1;
+  hadc3.Init.DiscontinuousConvMode = DISABLE;
+  hadc3.Init.NbrOfDiscConversion = 1;
+  hadc3.Init.ExternalTrigConv = ADC_SOFTWARE_START;
+  hadc3.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
+  hadc3.Init.DMAContinuousRequests = DISABLE;
+  hadc3.Init.Overrun = ADC_OVR_DATA_PRESERVED;
+  hadc3.Init.OversamplingMode = ENABLE;
+  hadc3.Init.Oversampling.Ratio = ADC_OVERSAMPLING_RATIO_16;
+  hadc3.Init.Oversampling.RightBitShift = ADC_RIGHTBITSHIFT_4;
+  hadc3.Init.Oversampling.TriggeredMode = ADC_TRIGGEREDMODE_SINGLE_TRIGGER;
+  hadc3.Init.Oversampling.OversamplingStopReset = ADC_REGOVERSAMPLING_RESUMED_MODE;
+
+  if (HAL_ADC_Init(&hadc3) != HAL_OK)
+  {
+    Error_Handler();
+  }
+
+  HAL_ADCEx_Calibration_Start(&hadc3, ADC_SINGLE_ENDED);
+
+  /** Configure Regular Channel
+  */
+  sConfig.Channel = ADC_CHANNEL_VBAT;
+  sConfig.Rank = ADC_REGULAR_RANK_1;
+  sConfig.SamplingTime = ADC_SAMPLETIME_640CYCLES_5;
+  sConfig.SingleDiff = ADC_SINGLE_ENDED;
+  sConfig.OffsetNumber = ADC_OFFSET_NONE;
+  sConfig.Offset = 0;
+  if (HAL_ADC_ConfigChannel(&hadc3, &sConfig) != HAL_OK)
+  {
+    Error_Handler();
+  }
+  /* USER CODE BEGIN ADC3_Init 2 */
+  ADC123_COMMON->CCR &= ~ADC_CCR_VBATEN;
+  /* USER CODE END ADC3_Init 2 */
+
+}
+
 /**
  * @brief CRC Initialization Function
  * @param None
--- a/mk4-time/Core/Src/qspi_drv.c
+++ b/mk4-time/Core/Src/qspi_drv.c
@@ -10,8 +10,8 @@ static QSPI_STATUS QSPI_Write_Page(uint8_t *pData, uint32_t address);

 uint8_t initialized = 0;
 uint8_t locked = 0;
-uint32_t qspi_write_time = 0;
-uint32_t qspi_usb_read_time = 0;
+volatile uint32_t qspi_write_time = 0;
+volatile uint32_t qspi_usb_read_time = 0;

 uint8_t QSPI_Initialized()
 {
--- a/mk4-time/Core/Src/stm32l4xx_hal_msp.c
+++ b/mk4-time/Core/Src/stm32l4xx_hal_msp.c
@@ -94,6 +94,8 @@ void HAL_MspInit(void)
  /* USER CODE END MspInit 1 */
 }

+static uint32_t HAL_RCC_ADC_CLK_ENABLED=0;
+
 /**
 * @brief ADC MSP Initialization
 * This function configures the hardware resources used in this example
@@ -109,7 +111,10 @@ void HAL_ADC_MspInit(ADC_HandleTypeDef* hadc)

  /* USER CODE END ADC1_MspInit 0 */
    /* Peripheral clock enable */
-    __HAL_RCC_ADC_CLK_ENABLE();
+    HAL_RCC_ADC_CLK_ENABLED++;
+    if(HAL_RCC_ADC_CLK_ENABLED==1){
+      __HAL_RCC_ADC_CLK_ENABLE();
+    }

    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**ADC1 GPIO Configuration
@@ -124,6 +129,20 @@ void HAL_ADC_MspInit(ADC_HandleTypeDef* hadc)

  /* USER CODE END ADC1_MspInit 1 */
  }
+  else if(hadc->Instance==ADC3)
+  {
+  /* USER CODE BEGIN ADC3_MspInit 0 */
+
+  /* USER CODE END ADC3_MspInit 0 */
+    /* Peripheral clock enable */
+    HAL_RCC_ADC_CLK_ENABLED++;
+    if(HAL_RCC_ADC_CLK_ENABLED==1){
+      __HAL_RCC_ADC_CLK_ENABLE();
+    }
+  /* USER CODE BEGIN ADC3_MspInit 1 */
+
+  /* USER CODE END ADC3_MspInit 1 */
+  }

 }

@@ -141,7 +160,10 @@ void HAL_ADC_MspDeInit(ADC_HandleTypeDef* hadc)

  /* USER CODE END ADC1_MspDeInit 0 */
    /* Peripheral clock disable */
-    __HAL_RCC_ADC_CLK_DISABLE();
+    HAL_RCC_ADC_CLK_ENABLED--;
+    if(HAL_RCC_ADC_CLK_ENABLED==0){
+      __HAL_RCC_ADC_CLK_DISABLE();
+    }

    /**ADC1 GPIO Configuration
    PA5     ------> ADC1_IN10
@@ -152,6 +174,20 @@ void HAL_ADC_MspDeInit(ADC_HandleTypeDef* hadc)

  /* USER CODE END ADC1_MspDeInit 1 */
  }
+  else if(hadc->Instance==ADC3)
+  {
+  /* USER CODE BEGIN ADC3_MspDeInit 0 */
+
+  /* USER CODE END ADC3_MspDeInit 0 */
+    /* Peripheral clock disable */
+    HAL_RCC_ADC_CLK_ENABLED--;
+    if(HAL_RCC_ADC_CLK_ENABLED==0){
+      __HAL_RCC_ADC_CLK_DISABLE();
+    }
+  /* USER CODE BEGIN ADC3_MspDeInit 1 */
+
+  /* USER CODE END ADC3_MspDeInit 1 */
+  }

 }

--- a/mk4-time/Core/Src/stm32l4xx_it.c
+++ b/mk4-time/Core/Src/stm32l4xx_it.c
@@ -44,7 +44,7 @@

 /* Private variables ---------------------------------------------------------*/
 /* USER CODE BEGIN PV */
-uint8_t delayButtonPress=0;
+
 /* USER CODE END PV */

 /* Private function prototypes -----------------------------------------------*/
@@ -69,7 +69,8 @@ extern UART_HandleTypeDef huart1;
 extern UART_HandleTypeDef huart2;
 /* USER CODE BEGIN EV */
 extern uint8_t nmea[90];
-extern uint8_t GPS_sv, GLONASS_sv;
+extern uint8_t satview[SV_COUNT];
+extern uint8_t satview_stale;
 extern uint16_t buffer_adc[ADC_BUFFER_SIZE];
 extern uint16_t buffer_dac[DAC_BUFFER_SIZE];
 extern DAC_HandleTypeDef hdac1;
@@ -80,8 +81,8 @@ extern _Bool data_valid, had_pps;
 extern uint8_t decisec, centisec, millisec;
 extern uint8_t displayMode, countMode, nmea_cdc_level;

-extern uint32_t qspi_write_time;
-extern uint32_t qspi_usb_read_time;
+extern volatile uint32_t qspi_write_time;
+extern volatile uint32_t qspi_usb_read_time;

 /* USER CODE END EV */

@@ -205,18 +206,30 @@ void PendSV_Handler(void)
  // Writing to the RTC is normally very fast, but if something goes wrong
  // the HAL functions will fail to time out if it's running with the same
  // preemption priority as systick
-  if (had_pps) write_rtc();
+  if (had_pps && !qspi_write_time && !qspi_usb_read_time) write_rtc();

  //if (buffer_c[3].high & cSegDP) buffer_c[3].high&=~cSegDP; else buffer_c[3].high|=cSegDP;

-  if (delayButtonPress & 1) {  delayButtonPress &= ~1; button1pressed(); }
-  if (delayButtonPress & 2) {  delayButtonPress &= ~2; button2pressed(); }
+  if (waitingForLatch) {
+    // in the specific case of countdown reaching zero, it will leave the latch hanging
+    sendLatch()
+    waitingForLatch=0;
+  }

  setPrecision();

-  if (displayMode==MODE_SHOW_OFFSET) {sendDate(1);}
+  if (resendDate) {sendDate(1); resendDate=0;}

-  GLONASS_sv = 255; GPS_sv = 255;
+  if (satview_stale>3){
+    satview[SV_GPS_L1]=255;
+    satview[SV_GPS_UNKNOWN]=255;
+    satview[SV_GLONASS_L1]=255;
+    satview[SV_GLONASS_UNKNOWN]=255;
+    satview[SV_GALILEO_E1]=255;
+    satview[SV_GALILEO_UNKNOWN]=255;
+    satview[SV_BEIDOU_B1]=255;
+    satview[SV_BEIDOU_UNKNOWN]=255;
+  } else satview_stale++;

  /* USER CODE END PendSV_IRQn 0 */
  /* USER CODE BEGIN PendSV_IRQn 1 */
@@ -357,7 +370,7 @@ void USART1_IRQHandler(void)
   && nmea[3]=='G'
   && nmea[4]=='S'
   && nmea[5]=='V')
-    decodeGSV();
+    decodeGSV(rec);


  HAL_UART_AbortReceive(&huart1);
@@ -385,12 +398,9 @@ void USART2_IRQHandler(void)

    uint8_t x = (USART2->RDR &0xFF);
    if (x == 0x91) {
-      // if we're beyond 0.9 seconds the date side will already be waiting for latch
-      if (decisec==9 && countMode!=COUNT_HIDDEN) delayButtonPress |= 1;
-      else button1pressed();
+        button1pressed();
    } else if (x == 0x92) {
-      if (decisec==9 && countMode!=COUNT_HIDDEN) delayButtonPress |= 2;
-      else button2pressed();
+        button2pressed();
    }
    return;
  }
--- a/mk4-time/Core/Src/sysmem.c
+++ b/mk4-time/Core/Src/sysmem.c
@@ -24,6 +24,7 @@
 /* Includes */
 #include <errno.h>
 #include <stdio.h>
+#include <sys/types.h>

 /* Variables */
 extern int errno;
--- a/mk4-time/Core/Src/version.c
+++ b/mk4-time/Core/Src/version.c
@@ -1,3 +1,4 @@
 // in pre-build steps: rm -f Core/Src/version.o

+#define VERSION_STRING "Version 0.0.1 "
 #include "../../../version.h"
--- a/mk4-time/Core/Src/zonedetect.c
+++ b/mk4-time/Core/Src/zonedetect.c
@@ -80,8 +80,8 @@ struct ZoneDetectOpaque {
 uint8_t mapCache[MAP_CACHE_SIZE];
 uint32_t mapCacheStart = 0xffffffff, mapCacheEnd = 0;

-extern uint32_t qspi_write_time;
-extern uint32_t qspi_usb_read_time;
+extern volatile uint32_t qspi_write_time;
+extern volatile uint32_t qspi_usb_read_time;

 volatile _Bool zd_abort =0;
 void ZDAbort(){
--- a/mk4-time/mk4-time.ioc
+++ b/mk4-time/mk4-time.ioc
@@ -9,6 +9,15 @@ ADC1.Overrun=ADC_OVR_DATA_OVERWRITTEN
 ADC1.Rank-0\#ChannelRegularConversion=1
 ADC1.SamplingTime-0\#ChannelRegularConversion=ADC_SAMPLETIME_92CYCLES_5
 ADC1.master=1
+ADC3.Channel-0\#ChannelRegularConversion=ADC_CHANNEL_VBAT
+ADC3.IPParameters=Rank-0\#ChannelRegularConversion,Channel-0\#ChannelRegularConversion,SamplingTime-0\#ChannelRegularConversion,OffsetNumber-0\#ChannelRegularConversion,NbrOfConversionFlag
+ADC3.NbrOfConversionFlag=1
+ADC3.OffsetNumber-0\#ChannelRegularConversion=ADC_OFFSET_NONE
+ADC3.Rank-0\#ChannelRegularConversion=1
+ADC3.SamplingTime-0\#ChannelRegularConversion=ADC_SAMPLETIME_2CYCLES_5
+CAD.formats=
+CAD.pinconfig=
+CAD.provider=
 CRC.IPParameters=InputDataInversionMode,OutputDataInversionMode,InputDataFormat
 CRC.InputDataFormat=CRC_INPUTDATA_FORMAT_WORDS
 CRC.InputDataInversionMode=CRC_INPUTDATA_INVERSION_BYTE
@@ -94,28 +103,30 @@ FATFS._MIN_SS=4096
 File.Version=6
 GPIO.groupedBy=Group By Peripherals
 KeepUserPlacement=false
+Mcu.CPN=STM32L476RGT3
 Mcu.Family=STM32L4
 Mcu.IP0=ADC1
-Mcu.IP1=CRC
-Mcu.IP10=SYS
-Mcu.IP11=TIM1
-Mcu.IP12=TIM2
-Mcu.IP13=TIM5
-Mcu.IP14=TIM6
-Mcu.IP15=TIM7
-Mcu.IP16=USART1
-Mcu.IP17=USART2
-Mcu.IP18=USB_DEVICE
-Mcu.IP19=USB_OTG_FS
-Mcu.IP2=DAC1
-Mcu.IP3=DMA
-Mcu.IP4=FATFS
-Mcu.IP5=LPTIM1
-Mcu.IP6=NVIC
-Mcu.IP7=QUADSPI
-Mcu.IP8=RCC
-Mcu.IP9=RTC
-Mcu.IPNb=20
+Mcu.IP1=ADC3
+Mcu.IP10=RTC
+Mcu.IP11=SYS
+Mcu.IP12=TIM1
+Mcu.IP13=TIM2
+Mcu.IP14=TIM5
+Mcu.IP15=TIM6
+Mcu.IP16=TIM7
+Mcu.IP17=USART1
+Mcu.IP18=USART2
+Mcu.IP19=USB_DEVICE
+Mcu.IP2=CRC
+Mcu.IP20=USB_OTG_FS
+Mcu.IP3=DAC1
+Mcu.IP4=DMA
+Mcu.IP5=FATFS
+Mcu.IP6=LPTIM1
+Mcu.IP7=NVIC
+Mcu.IP8=QUADSPI
+Mcu.IP9=RCC
+Mcu.IPNb=21
 Mcu.Name=STM32L476R(C-E-G)Tx
 Mcu.Package=LQFP64
 Mcu.Pin0=PC13
@@ -159,51 +170,52 @@ Mcu.Pin42=PB6
 Mcu.Pin43=PB7
 Mcu.Pin44=PB8
 Mcu.Pin45=PB9
-Mcu.Pin46=VP_CRC_VS_CRC
-Mcu.Pin47=VP_FATFS_VS_Generic
-Mcu.Pin48=VP_LPTIM1_VS_LPTIM_counterModeInternalClock
-Mcu.Pin49=VP_RTC_VS_RTC_Activate
+Mcu.Pin46=VP_ADC3_Vbat_Input
+Mcu.Pin47=VP_CRC_VS_CRC
+Mcu.Pin48=VP_FATFS_VS_Generic
+Mcu.Pin49=VP_LPTIM1_VS_LPTIM_counterModeInternalClock
 Mcu.Pin5=PC0
-Mcu.Pin50=VP_SYS_VS_Systick
-Mcu.Pin51=VP_TIM1_VS_ClockSourceINT
-Mcu.Pin52=VP_TIM5_VS_ClockSourceINT
-Mcu.Pin53=VP_TIM5_VS_no_output1
-Mcu.Pin54=VP_TIM5_VS_no_output2
-Mcu.Pin55=VP_TIM6_VS_ClockSourceINT
-Mcu.Pin56=VP_TIM7_VS_ClockSourceINT
-Mcu.Pin57=VP_USB_DEVICE_VS_USB_DEVICE_MSC_FS
+Mcu.Pin50=VP_RTC_VS_RTC_Activate
+Mcu.Pin51=VP_SYS_VS_Systick
+Mcu.Pin52=VP_TIM1_VS_ClockSourceINT
+Mcu.Pin53=VP_TIM5_VS_ClockSourceINT
+Mcu.Pin54=VP_TIM5_VS_no_output1
+Mcu.Pin55=VP_TIM5_VS_no_output2
+Mcu.Pin56=VP_TIM6_VS_ClockSourceINT
+Mcu.Pin57=VP_TIM7_VS_ClockSourceINT
+Mcu.Pin58=VP_USB_DEVICE_VS_USB_DEVICE_MSC_FS
 Mcu.Pin6=PC1
 Mcu.Pin7=PC2
 Mcu.Pin8=PC3
 Mcu.Pin9=PA0
-Mcu.PinsNb=58
+Mcu.PinsNb=59
 Mcu.ThirdPartyNb=0
 Mcu.UserConstants=
 Mcu.UserName=STM32L476RGTx
 MxCube.Version=5.6.0
 MxDb.Version=DB.5.0.60
-NVIC.BusFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false
-NVIC.DMA1_Channel3_IRQn=true\:1\:0\:true\:false\:true\:false\:true
-NVIC.DMA1_Channel4_IRQn=true\:0\:0\:false\:false\:true\:false\:true
-NVIC.DMA1_Channel5_IRQn=true\:0\:0\:false\:false\:true\:false\:true
-NVIC.DMA1_Channel6_IRQn=true\:0\:0\:false\:false\:true\:false\:true
-NVIC.DMA1_Channel7_IRQn=true\:0\:0\:false\:false\:true\:false\:true
-NVIC.DMA2_Channel4_IRQn=true\:0\:0\:false\:false\:true\:false\:true
-NVIC.DMA2_Channel5_IRQn=true\:0\:0\:false\:false\:true\:false\:true
-NVIC.DebugMonitor_IRQn=true\:0\:0\:false\:false\:true\:false\:false
+NVIC.BusFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
+NVIC.DMA1_Channel3_IRQn=true\:1\:0\:true\:false\:true\:false\:true\:true
+NVIC.DMA1_Channel4_IRQn=true\:0\:0\:false\:false\:true\:false\:true\:true
+NVIC.DMA1_Channel5_IRQn=true\:0\:0\:false\:false\:true\:false\:true\:true
+NVIC.DMA1_Channel6_IRQn=true\:0\:0\:false\:false\:true\:false\:true\:true
+NVIC.DMA1_Channel7_IRQn=true\:0\:0\:false\:false\:true\:false\:true\:true
+NVIC.DMA2_Channel4_IRQn=true\:0\:0\:false\:false\:true\:false\:true\:true
+NVIC.DMA2_Channel5_IRQn=true\:0\:0\:false\:false\:true\:false\:true\:true
+NVIC.DebugMonitor_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
 NVIC.ForceEnableDMAVector=true
-NVIC.HardFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false
-NVIC.LPTIM1_IRQn=true\:1\:0\:true\:false\:true\:true\:true
-NVIC.MemoryManagement_IRQn=true\:0\:0\:false\:false\:true\:false\:false
-NVIC.NonMaskableInt_IRQn=true\:0\:0\:false\:false\:true\:false\:false
-NVIC.OTG_FS_IRQn=true\:1\:0\:true\:false\:true\:false\:true
-NVIC.PendSV_IRQn=true\:2\:0\:true\:false\:true\:false\:false
+NVIC.HardFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
+NVIC.LPTIM1_IRQn=true\:1\:0\:true\:false\:true\:true\:true\:true
+NVIC.MemoryManagement_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
+NVIC.NonMaskableInt_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
+NVIC.OTG_FS_IRQn=true\:1\:0\:true\:false\:true\:false\:true\:true
+NVIC.PendSV_IRQn=true\:2\:0\:true\:false\:true\:false\:false\:false
 NVIC.PriorityGroup=NVIC_PRIORITYGROUP_4
-NVIC.SVCall_IRQn=true\:0\:0\:false\:false\:true\:false\:false
-NVIC.SysTick_IRQn=true\:0\:0\:true\:false\:false\:false\:false
-NVIC.USART1_IRQn=true\:1\:0\:true\:false\:true\:true\:false
-NVIC.USART2_IRQn=true\:0\:0\:false\:false\:true\:true\:true
-NVIC.UsageFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false
+NVIC.SVCall_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
+NVIC.SysTick_IRQn=true\:0\:0\:true\:false\:false\:false\:false\:false
+NVIC.USART1_IRQn=true\:1\:0\:true\:false\:true\:true\:false\:true
+NVIC.USART2_IRQn=true\:0\:0\:false\:false\:true\:true\:true\:true
+NVIC.UsageFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
 PA0.Signal=S_TIM2_CH1
 PA1.Signal=S_TIM2_CH2
 PA10.Mode=Asynchronous
@@ -322,10 +334,13 @@ ProjectManager.PreviousToolchain=
 ProjectManager.ProjectBuild=false
 ProjectManager.ProjectFileName=mk4-time.ioc
 ProjectManager.ProjectName=mk4-time
+ProjectManager.ProjectStructure=
 ProjectManager.RegisterCallBack=
 ProjectManager.StackSize=0x400
 ProjectManager.TargetToolchain=STM32CubeIDE
 ProjectManager.ToolChainLocation=
+ProjectManager.UAScriptAfterPath=
+ProjectManager.UAScriptBeforePath=
 ProjectManager.UnderRoot=true
 ProjectManager.functionlistsort=1-MX_GPIO_Init-GPIO-false-HAL-true,2-MX_DMA_Init-DMA-false-HAL-true,3-SystemClock_Config-RCC-false-HAL-false,4-MX_QUADSPI_Init-QUADSPI-false-HAL-true,5-MX_TIM1_Init-TIM1-false-HAL-true,6-MX_USART2_UART_Init-USART2-false-HAL-true,7-MX_FATFS_Init-FATFS-false-HAL-false,8-MX_USB_DEVICE_Init-USB_DEVICE-false-HAL-false,9-MX_USART1_UART_Init-USART1-false-HAL-true,10-MX_TIM2_Init-TIM2-false-HAL-true,11-MX_ADC1_Init-ADC1-false-HAL-true,12-MX_DAC1_Init-DAC1-false-HAL-true,13-MX_TIM6_Init-TIM6-false-HAL-true,14-MX_RTC_Init-RTC-true-HAL-true,15-MX_TIM7_Init-TIM7-false-HAL-true,16-MX_CRC_Init-CRC-false-HAL-true,17-MX_LPTIM1_Init-LPTIM1-false-LL-true,18-MX_TIM5_Init-TIM5-false-HAL-true
 QUADSPI.ClockPrescaler-Single\ Bank=0
@@ -445,6 +460,8 @@ USB_DEVICE.VirtualMode=Msc
 USB_DEVICE.VirtualModeFS=Msc_FS
 USB_OTG_FS.IPParameters=VirtualMode
 USB_OTG_FS.VirtualMode=Device_Only
+VP_ADC3_Vbat_Input.Mode=IN-Vbat
+VP_ADC3_Vbat_Input.Signal=ADC3_Vbat_Input
 VP_CRC_VS_CRC.Mode=CRC_Activate
 VP_CRC_VS_CRC.Signal=CRC_VS_CRC
 VP_FATFS_VS_Generic.Mode=User_defined
@@ -470,3 +487,4 @@ VP_TIM7_VS_ClockSourceINT.Signal=TIM7_VS_ClockSourceINT
 VP_USB_DEVICE_VS_USB_DEVICE_MSC_FS.Mode=MSC_FS
 VP_USB_DEVICE_VS_USB_DEVICE_MSC_FS.Signal=USB_DEVICE_VS_USB_DEVICE_MSC_FS
 board=custom
+isbadioc=false
--- a/qspi/config.txt
+++ b/qspi/config.txt
@@ -8,6 +8,7 @@ MATRIX_FREQUENCY = 20000

 # Use this timezone, leave blank to calculate automatically
 # Must be an IANA timezone string, use e.g. Etc/GMT+5 for fixed offsets
+# For UTC use Etc/UTC
 #ZONE_OVERRIDE = America/New_York


@@ -19,13 +20,13 @@ MATRIX_FREQUENCY = 20000
 MODE_ISO8601_STD=Enabled

 # ISO8601 ordinal (day of year)
-MODE_ISO_Ordinal=Enabled
+MODE_ISO_Ordinal=disabled

 # ISO8601 week (year can be different around new year)
 MODE_ISO_WEEK = disabled

 # Unix timestamp mode. The unix timestamp is always UTC.
-MODE_UNIX = Enabled
+MODE_UNIX = Disabled

 # Julian Date
 MODE_JULIAN_DATE = disabled
@@ -40,14 +41,14 @@ MODE_SHOW_OFFSET = enabled
 # Attempt to display tz name on the 7-segment display, this is usually fairly illegible
 MODE_SHOW_TZ_NAME = enabled

-MODE_WEEKDAY = enabled
+MODE_WEEKDAY = disabled

 # Turn off all LEDs. This mode can be useful if you want to reduce power consumption
 # but keep the GPS module fully powered.
-MODE_STANDBY=Enabled
+MODE_STANDBY=disabled


-MODE_COUNTDOWN = on
+MODE_COUNTDOWN = off
 COUNTDOWN_TO = 2023-05-06T23:00:00Z


@@ -76,11 +77,12 @@ Tolerance_time_100ms = 100000


 # nonlinear brightness curve, five stops of input->output, use brightness-curve.htm for a GUI
-#BS1 = 0,0
-#BS2 = 1425,737
-#BS3 = 2566,1601
-#BS4 = 3396,2725
-#BS5 = 4095,4095
+# VTT9812FH with R11 = 470K
+BS1 = 0,0
+BS2 = 131,365
+BS3 = 1076,1422
+BS4 = 2774,2665
+BS5 = 3849,4095

 # shows input and output values of DAC/ADC
 MODE_DEBUG_BRIGHTNESS = 0
@@ -91,5 +93,8 @@ MODE_DEBUG_BRIGHTNESS = 0
 # show remainder of RTC calibration after 63 second period
 MODE_DEBUG_RTC = 0

-# list number of GPS/GLONASS satellites (number, not signal strength)
-mode_satview = 1
+# list number of satellites in view (number, not signal strength)
+mode_satview = 0
+
+# show coin cell voltage
+mode_vbat = 0
--- a/qspi/flash.sh
+++ b/qspi/flash.sh
@@ -37,6 +37,7 @@ function cleanup {
 trap cleanup EXIT

 sudo mkfs.fat -I -S 4096 "$dev"
+sudo fatlabel "$dev" CLOCK
 sudo mount "$dev" mnt/ # auto detects if loop device


--- a/qspi/output/fwd.bin
+++ b/qspi/output/fwd.bin
--- a/qspi/output/fwt.bin
+++ b/qspi/output/fwt.bin
--- a/qspi/output/tzmap.bin
+++ b/qspi/output/tzmap.bin
--- a/qspi/output/tzrules.bin
+++ b/qspi/output/tzrules.bin
--- a/qspi/qspi.md
+++ b/qspi/qspi.md
@@ -17,7 +17,7 @@ To run the builder install shapelib (and I had to add `#include <cstdint>`)

 Rename `out/timezone21.bin` to `tzmap.bin`

-The `out_v1/` format is smaller but takes longer to parse on the clock, so use the 11MB version.
+The `out_v1/` format is smaller but takes longer to parse on the clock, so use the `out/` version.

 Natural earth data is used only for the "country" database which isn't used here. All data comes from https://github.com/evansiroky/timezone-boundary-builder

@@ -28,7 +28,7 @@ We need to match the zones in the shapefile, so it now uses the `timezone-names.

 E.g.
 ```
-curl -L https://github.com/evansiroky/timezone-boundary-builder/releases/download/2023b/timezone-names.json | jq '.' > timezone-names.json
+curl -L https://github.com/evansiroky/timezone-boundary-builder/releases/download/2025b/timezone-names.json | jq '.' > timezone-names.json
 ```

 The `generate-tzrules.py` file uses these names and the installed timezone database on the system it's running. Query the tzdata package to see the version (`pacman -Q tzdata` or `apt show tzdata`)
@@ -48,4 +48,4 @@ Both firmware images are unencrypted/unobfuscated, but the last 32bit word of ea
 The update is performed if the CRC of the image in external flash is valid and different to the CRC of the loaded image, so downgrades are easy.

 ## loop device to create disk image
-`create-image.sh` will create a correctly formatted 16MB disk image of the QSPI contents using a loop device. The resulting image can be written using `dd` or some other disk image utility, which may be more convenient on other platforms.
+`./flash.sh loop` will create a correctly formatted 16MB disk image of the QSPI contents using a loop device. The resulting image can be written using `dd` or some other disk image utility, which may be more convenient on other platforms.
--- a/qspi/timezone-names.json
+++ b/qspi/timezone-names.json
@@ -90,6 +90,7 @@
  "America/Chihuahua",
  "America/Ciudad_Juarez",
  "America/Costa_Rica",
+  "America/Coyhaique",
  "America/Creston",
  "America/Cuiaba",
  "America/Curacao",
@@ -223,7 +224,6 @@
  "Asia/Bishkek",
  "Asia/Brunei",
  "Asia/Chita",
-  "Asia/Choibalsan",
  "Asia/Colombo",
  "Asia/Damascus",
  "Asia/Dhaka",
--- a/readme.md
+++ b/readme.md
@@ -0,0 +1,13 @@
+# Precision Clock Mk IV
+
+Source code for the [Precision Clock Mk IV](https://mitxela.com/projects/precision_clock_mk_iv)
+
+There are three software projects, compiled with STM32CubeIDE:
+
+- mk4-time is the main clock source code running on the STM32L476
+- mk4-date is the secondary display running on the STM32L010
+- mk4-bootloader runs on the STM32L476 to do firmware updates
+
+In the QSPI folder, there are scripts to create firmware images with CRC that the clock will recognise, along with the scripts to create the tzrules and create a valid disk image, see [these notes](qspi/qspi.md) for more info.
+
+Timezone detection is ported from [ZoneDetect](https://github.com/BertoldVdb/ZoneDetect) by Bertold Van den Bergh and uses shapefile data from [Timezone Boundary Builder](https://github.com/evansiroky/timezone-boundary-builder) by Evan Siroky.
Author	SHA1	Message	Date
mitxela	8af0b73a77	typo in hinge.svg Black 6mm rectangle should have a height of 22.56, with the lower hole 6mm from the bottom, and the top hole 5.28 from the top. It was off by 0.28mm so hardly noticable with the kerf of the laser, but we may as well make it exact.	2025-10-08 12:07:19 +01:00
mitxela	0dc65df840	Add redrawn STEP files These don't exactly match the STL files although both will work. STL files were generated from the OpenSCAD file. STEP files were redrawn with some fillets and other tweaks, moving forwards the step files may be the main reference	2025-10-08 11:55:02 +01:00
mitxela	9e6b0c1afa	Move main STL files into folders for rev C, rev D	2025-10-08 11:54:08 +01:00
mitxela	f5113a92e4	Set brightness curve in config file for phototransistor The default curve in the firmware, with nothing specified in the config file (or this commented out) matches the LDR.	2025-10-08 11:24:02 +01:00
mitxela	67010598d9	add STL for phototransistor (VTT9812FH)	2025-10-08 11:08:22 +01:00
mitxela	70c04301dc	bootloader user request on PA2/hinge TX	2025-08-03 12:21:24 +01:00
mitxela	b7e80f0d8d	update config.txt template	2025-08-02 14:34:22 +01:00
mitxela	22cb434297	inc fwt version	2025-08-02 14:18:12 +01:00
mitxela	c632fc4c28	wipe vbat measurement on leaving mode_vbat	2025-08-02 01:39:14 +01:00
mitxela	b3e00fb43c	Reduce power-on precision if coin cell below 2.7V	2025-08-02 01:26:30 +01:00
mitxela	914471d6f3	oversampling vbat is substantially more stable	2025-08-01 19:37:36 +01:00
mitxela	922586d549	mode_vbat	2025-08-01 19:28:59 +01:00
mitxela	6ee513efb1	initial vbat reading using adc3	2025-08-01 16:04:12 +01:00
mitxela	c3e81356f5	monitor beidou, plot gps and the highest non-gps satview	2025-08-01 11:43:28 +01:00
mitxela	384b85b9f9	further complication of GSV parsing signal ID is not always present, number of fields is variable, what was meant to be a quick way of showing number of satellites is becoming a mess	2025-08-01 11:05:25 +01:00
mitxela	f4751fce09	correctly interpret multiple GSV messages M10 gps module sends GPGSV multiple times in separate groups, even though it's only listening to a single band.	2025-08-01 02:16:35 +01:00
mitxela	b30b862fda	latch satview ublox 10 series output GSV only every 5 seconds	2025-08-01 01:22:08 +01:00
mitxela	74f683c7ba	update qspi.md	2025-07-31 23:24:44 +01:00
mitxela	43cdfe10cc	tzmap 2025b (full)	2025-07-31 22:37:14 +01:00
mitxela	6ba38a7a55	tzrules to 2025b	2025-07-31 13:58:19 +01:00
mitxela	05ab0d7123	update timezone-names to 2025b	2025-07-31 13:45:09 +01:00
mitxela	529555730a	Bootloader updates to explicitly protect the stack Using both noreturn and __builting_unreachable() is superfluous but hopefully makes it twice as unlikely to optimise the jump into a tail call. Not sure if this is better than -O0 but hopefully makes some people less unhappy.	2025-07-31 11:20:20 +01:00
mitxela	fa71140552	add physical dimensions to hinge svg	2025-07-31 10:47:49 +01:00
mitxela	0d76b0f078	generate either version in openscad	2025-07-31 10:26:48 +01:00
mitxela	f2cc1f54ab	cad for vtt9812fh	2025-07-25 11:03:43 +01:00
mitxela	eca890e2b2	a dubiously helpful overlay for brightness curve	2025-07-18 12:20:23 +01:00
mitxela	fd62ade91b	method to convert a bunch of brightness values	2025-07-18 12:01:34 +01:00
mitxela	4fb73649ea	basic support for touchscreen devices	2025-07-12 23:21:57 +01:00
mitxela	3bc2ccb08b	allow pasting in brightness curve values	2025-07-12 22:30:21 +01:00
mitxela	90ac0fc267	generate binary files	2025-07-04 17:43:42 +01:00
mitxela	8ce8a867d1	compatibility with toolchain 12.3.rel1	2025-07-04 17:42:04 +01:00
mitxela	715e8b338d	Ignore env hashes using clean/smudge filter Add following to .git/config: [filter "eclipse_env_hash"] clean = sed 's/env-hash=\"[-,0-9]*\"/env-hash=\"0000000000000000000\"/g' smudge = cat	2025-07-04 17:25:38 +01:00
mitxela	2571e62078	Revert "Don't track these IDE files that keep changing" This reverts commit `8e4d62cca4`.	2025-07-04 17:08:06 +01:00
mitxela	7a0fc54fa8	add shelfstand cad files	2025-06-29 18:19:36 +01:00
mitxela	a1e8af3cf9	Add handcrafted SVG version of moshidraw hinge	2025-06-29 17:58:50 +01:00
mitxela	122e601da9	add readme	2025-05-25 12:36:35 +01:00
mitxela	4ce85147f0	CAD files for antenna case Specifically for the patch antenna with SMA connector crimped as close as possible. Top half (caset.stl) needs to be printed upside down with support for the cable shroud. Last modified 2023-04-19	2025-05-21 12:56:06 +01:00
mitxela	16edb66444	Add cad files for wall hangers	2025-05-21 12:49:25 +01:00
mitxela	7c9b9b6f0e	lasercut files update for easier tiling	2025-05-21 12:24:08 +01:00
mitxela	c46e7cc803	Add moshidraw file for hinge (convert to DXF or SVG later)	2025-05-21 12:23:17 +01:00
mitxela	2dd441d178	make colon cover a teeny bit taller	2025-05-21 12:07:35 +01:00
mitxela	4c8d2fa190	add side cutouts to colons for better pliability	2025-05-21 12:06:07 +01:00
mitxela	fb0785b312	flat-top LEDs have 3.15 dia	2025-05-21 12:04:07 +01:00
mitxela	ed93d83036	commit STL files	2025-05-21 12:02:56 +01:00
mitxela	65bb96ff6f	cad updates from 2023-06-15	2025-05-21 11:52:47 +01:00
mitxela	30425af408	start adding cad files to this repo	2025-05-21 11:37:13 +01:00
mitxela	8e4d62cca4	Don't track these IDE files that keep changing	2024-10-22 11:17:51 +01:00
mitxela	29691bc5bc	Add known firmware images to repo (2024-05-29)	2024-10-22 11:09:33 +01:00
mitxela	9007c9be64	Config file defaults, most modes off	2024-06-27 10:59:05 +01:00
mitxela	0d7561f1ab	IDE settings (unsure what changed)	2024-06-27 10:31:14 +01:00
mitxela	e380791170	slightly smaller hammer (re: `b91a100`)	2024-06-27 10:29:33 +01:00
mitxela	b91a1004f9	sledgehammer to prevent -Os trashing launch_app()	2024-06-27 10:21:34 +01:00
mitxela	3a3db5b583	suppress maybe-uninitialised warning	2024-06-27 10:20:54 +01:00
mitxela	c110cc0b47	Pad bootloader to exactly 64K	2024-06-27 10:20:14 +01:00
mitxela	5c84802a9e	Bootloader version string	2024-06-26 09:34:19 +01:00
mitxela	7b388bc2b6	env hash stuff - should probably ignore these files	2024-06-26 09:33:34 +01:00
mitxela	ea364d761a	partial changes to bootloader - unfinished f_mount doesn't actually do anything until first read (unless forced) so it's not really possible to error out at the mount stage, but we don't want any possible way to hang without enabling usb	2023-08-25 13:40:06 +01:00
mitxela	12565ff862	Clear colons in bootloader They are off when tristated too but need to be explicitly high to remain off on the xl	2023-07-27 13:20:23 +01:00
mitxela	a11f54b005	and volatile again in the bootloader This was working without it, so the fix is hypothetical. Might be because bootloader is -Os and time is -O3	2023-07-26 12:33:27 +01:00
mitxela	344aa32ddd	another volatile optimisation victim	2023-07-25 23:12:37 +01:00
mitxela	2510c85b26	set volume label to CLOCK	2023-07-25 11:47:03 +01:00
mitxela	99af17dd31	blank date when updating on eject	2023-07-24 16:02:58 +01:00
mitxela	ce4fd5172f	delay setDisplayFrequency if needed	2023-07-24 15:24:12 +01:00
mitxela	a9490dbee4	Don't write RTC during USB read/writes, pendSV could be delayed	2023-07-24 13:34:06 +01:00
mitxela	cc5e7114b8	fix countdown mode entering/exiting	2023-07-24 13:32:20 +01:00
mitxela	2a04bc99a1	Replace delayedButtonPress with resendDate Not sure if this is better than the alternative, that is to delay CDC commands and reloaded config too. Todo: countdown mode fixes	2023-07-23 16:50:37 +01:00
mitxela	95c0565fab	Measure lookup time macro Takes 3x longer if launched via swd instead of bootloader. QSPI quad read seems to make it slower. Definitely something odd going on	2023-07-21 16:25:53 +01:00
				`@@ -0,0 +1 @@`
				`*/.settings/language.settings.xml filter=eclipse_env_hash`