More bugfixes for the SD card. It was failing to mount with the delay…

…s given
danieldegrasse · Aug 13, 2020 · 0d6a0ac · 0d6a0ac
1 parent 37bb1be
commit 0d6a0ac
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Showing 2 changed files with 16 additions and 25 deletions.
diff --git a/sd_card.c b/sd_card.c
@@ -86,33 +86,19 @@ bool attempt_sd_mount(void) {
         return SD_CARD_MOUNTED;
     }
     /**
-     * The power toggle sequence below is required because the MCU will reset
-     * if the SD card is plugged in while power is supplied to the SD card.
-     * Therefore, we keep the power to the card disabled until a mount of it
-     * is requested. The power off here is precautionary, the SD card should
-     * not be powered at this point.
+     * 
+     * The SD Card needs to be aware of the SPI signal before it is powered.
+     * If the SPI bus has not been setup, it will not be and the MCU will
+     * reset.
+     * 
+     * Delay for 1000ms to let the SD card see the bus.
+     * Don't shorten this delay, I tried and the card needs time to *think*
      */
-    // Power off the SD card by disabling the VCC pin.
-    GPIO_write(Board_SDCARD_VCC, Board_LED_OFF);
+    // Power up the SD card
+    GPIO_write(Board_SDCARD_VCC, Board_LED_ON);
     /* Try to mount the SD card. */
     SDSPI_Params_init(&sdspi_params);
     SDSPI_HANDLE = SDSPI_open(Board_SDSPI0, DRIVE_NUM, &sdspi_params);
-    if (FIRST_INIT) {
-        /**
-         * FIRST_INIT tracks if the SPI Bus has been setup for the SD card.
-         * 
-         * The SD Card needs to be aware of the SPI signal before it is powered.
-         * If the SPI bus has not been setup, it will not be and the MCU will
-         * reset.
-         * 
-         * Delay for 1000ms to let the SD card see the bus.
-         * Don't shorten this delay, I tried and the card needs time to *think*
-         */
-        Task_sleep(1000);
-        FIRST_INIT = false;
-    }
-    // Now power up the SD card again.
-    GPIO_write(Board_SDCARD_VCC, Board_LED_ON);
     if (SDSPI_HANDLE == NULL) {
         System_abort("Error starting the SD card\n");
     } else {

diff --git a/uart_logger_task.c b/uart_logger_task.c
@@ -2,7 +2,7 @@
  * @file uart_logger.c
  * Implements the task responsible for reading data from a UART, and writing it
  * to an SD card log file.
- * 
+ *
  * Pins Required:
  * PC6- UART RX
  * PC7- UART TX
@@ -40,7 +40,7 @@ static UART_Params params;
  */
 void uart_logger_prebios(void) {
     /*
-     * UART defaults to text mode, echo back characters, and return from read 
+     * UART defaults to text mode, echo back characters, and return from read
      * after newline. Default 8 bits, one stop bit, no parity.
      */
     UART_Params_init(&params);
@@ -66,6 +66,11 @@ void uart_logger_prebios(void) {
  */
 void uart_logger_task_entry(UArg arg0, UArg arg1) {
     char read_buf[READSIZE];
+    /**
+     * Sleep for 100 ms. For some reason, the MCU resets if the SD card is
+     * powered up too soon.
+     */
+    Task_sleep(100);
     /*
      * Try to mount the SD card, and if it fails wait for the sd_ready
      * condition.