PPS via DCD experiments

mk4-time/Core/Src/stm32l4xx_it.c

@@ -45,6 +45,7 @@
 /* Private variables ---------------------------------------------------------*/
 /* USER CODE BEGIN PV */
 uint8_t delayButtonPress=0;
+_Bool CDC_Set = 0;
 /* USER CODE END PV */
 
 /* Private function prototypes -----------------------------------------------*/
@@ -76,7 +77,7 @@ extern DAC_HandleTypeDef hdac1;
 extern ADC_HandleTypeDef hadc1;
 extern float dac_target;
 extern uint8_t uart2_tx_buffer[32];
-extern _Bool data_valid, had_pps;
+extern _Bool data_valid, had_pps, last_pps_time, currentTime;
 extern uint8_t decisec, centisec, millisec;
 extern uint8_t displayMode, countMode, nmea_cdc_level;
 
@@ -193,6 +194,12 @@ void PendSV_Handler(void)
 {
   /* USER CODE BEGIN PendSV_IRQn 0 */
 
+  if (had_pps && last_pps_time == (uint32_t)currentTime) {
+    CDC_Transmit_serial_state(CDC_SERIAL_STATE_DCD);
+    CDC_Set=1;
+  }
+
+
   // 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
@@ -346,6 +353,10 @@ void USART1_IRQHandler(void)
    && nmea[5]=='V')
     decodeGSV();
 
+  if (CDC_Set && (GPIOC->IDR & GPIO_PIN_7)==0){
+    CDC_Transmit_serial_state(0);
+    CDC_Set=0;
+  }
 
   HAL_UART_AbortReceive(&huart1);
   HAL_UART_Receive_DMA(&huart1, nmea, sizeof(nmea));

mk4-time/Middlewares/ST/STM32_USB_Device_Library/Class/CDC/Inc/usbd_cdc.h

@@ -117,6 +117,7 @@ typedef struct
 
   __IO uint32_t TxState;
   __IO uint32_t RxState;
+  __IO uint32_t CMDState;
 }
 USBD_CDC_HandleTypeDef;
 

mk4-time/Middlewares/ST/STM32_USB_Device_Library/Class/CDC/Src/usbd_cdc.c

@@ -501,6 +501,7 @@ uint8_t  USBD_CDC_Init(USBD_HandleTypeDef *pdev, uint8_t cfgidx)
   /* Init Xfer states */
   hcdc->TxState = 0U;
   hcdc->RxState = 0U;
+  hcdc->CMDState= 0U;
 
   if (pdev->dev_speed == USBD_SPEED_HIGH)
   {
@@ -670,7 +671,10 @@ uint8_t  USBD_CDC_DataIn(USBD_HandleTypeDef *pdev, uint8_t epnum)
     }
     else
     {
-      hcdc->TxState = 0U;
+      if (epnum == (CDC_IN_EP & 0x7F))
+        hcdc->TxState = 0U;
+      else if (epnum == (CDC_CMD_EP & 0x7F))
+        hcdc->CMDState = 0U;
     }
     return USBD_OK;
   }

mk4-time/USB_DEVICE/App/usbd_cdc_if.c

@@ -24,6 +24,7 @@
 
 /* USER CODE BEGIN INCLUDE */
 #include "main.h"
+#include "usbd_msc_cdc.h"
 /* USER CODE END INCLUDE */
 
 /* Private typedef -----------------------------------------------------------*/
@@ -100,6 +101,15 @@ uint8_t UserTxBufferFS[APP_TX_DATA_SIZE];
 
 /* USER CODE BEGIN PRIVATE_VARIABLES */
 
+static struct serial_state {
+  uint8_t  bmRequestType;
+  uint8_t  bNotification;
+  uint16_t wValue;
+  uint16_t wIndex;
+  uint16_t wLength;
+  uint16_t state;
+} serial_state_msg;
+
 /* USER CODE END PRIVATE_VARIABLES */
 
 /**
@@ -133,6 +143,35 @@ static int8_t CDC_Receive_FS(uint8_t* pbuf, uint32_t *Len);
 
 /* USER CODE BEGIN PRIVATE_FUNCTIONS_DECLARATION */
 
+/**
+  * @brief  CDC_Transmit_serial_state
+  *         Sends the new serial state to the host
+  * @param  newstate: new state of CDC_SERIAL_STATE* flags
+  * @retval Result of the operation: USBD_OK if all operations are OK else USBD_FAIL
+  */
+uint8_t CDC_Transmit_serial_state(uint16_t newstate) {
+  USBD_CDC_HandleTypeDef *hcdc = (USBD_CDC_HandleTypeDef*)hUsbDeviceFS.pClassDataCDC;
+
+  if(hcdc == NULL)
+    return USBD_FAIL;
+
+  if(hcdc->CMDState != 0)
+    return USBD_BUSY;
+
+  /* CMD Transfer in progress */
+  hcdc->CMDState = 1;
+
+  serial_state_msg.bmRequestType = 0xA1;
+  serial_state_msg.bNotification = 0x20;
+  serial_state_msg.wValue = 0;
+  serial_state_msg.wIndex = 0; // interface
+  serial_state_msg.wLength = 2;
+  serial_state_msg.state = newstate;
+  USBD_LL_Transmit(&hUsbDeviceFS, CDC_CMD_EP, (uint8_t *)&serial_state_msg, 10);
+
+  return USBD_OK;
+}
+
 /* USER CODE END PRIVATE_FUNCTIONS_DECLARATION */
 
 /**

mk4-time/USB_DEVICE/App/usbd_cdc_if.h

@@ -50,6 +50,14 @@
   */
 /* USER CODE BEGIN EXPORTED_DEFINES */
 
+#define CDC_SERIAL_STATE_DCD     0b0000001
+#define CDC_SERIAL_STATE_DSR     0b0000010
+#define CDC_SERIAL_STATE_BREAK   0b0000100
+#define CDC_SERIAL_STATE_RING    0b0001000
+#define CDC_SERIAL_STATE_FRAME   0b0010000
+#define CDC_SERIAL_STATE_PARITY  0b0100000
+#define CDC_SERIAL_STATE_OVERRUN 0b1000000
+
 /* USER CODE END EXPORTED_DEFINES */
 
 /**
@@ -108,6 +116,7 @@ uint8_t CDC_Transmit_FS(uint8_t* Buf, uint16_t Len);
 /* USER CODE BEGIN EXPORTED_FUNCTIONS */
 
 uint8_t CDC_Copy_Transmit(uint8_t* nmea, uint16_t Len);
+uint8_t CDC_Transmit_serial_state(uint16_t newstate);
 
 /* USER CODE END EXPORTED_FUNCTIONS */