# HG changeset patch
# User Ideenmodellierer
# Date 1640111801 -3600
# Node ID 667093daa937c56629e80e4521af5357ab6bd585
# Parent  16833cd3a2f5ce86a77d9cbb9a9ef67f615ef490
Stability improvment bluetooth startup:
The previous implementation expected a default setup of the Bluetooth module. Deviations from the default expectation caused the init function to stop. The new implementation is able to fix wrong baud rate setting (reset baudrate to default 115200).
In addition the function evaluating the answers of the module is not able to derive the status out of a data stream.

diff -r 16833cd3a2f5 -r 667093daa937 Discovery/Src/tComm.c
--- a/Discovery/Src/tComm.c	Tue Dec 21 19:32:29 2021 +0100
+++ b/Discovery/Src/tComm.c	Tue Dec 21 19:36:41 2021 +0100
@@ -2001,7 +2001,8 @@
     char aRxBuffer[UART_CMD_BUF_SIZE];
     uint8_t sizeAnswer = sizeof(answerOkay) -1;
 	uint8_t result = HAL_OK;
-	uint8_t index = 0;
+	uint8_t indexRef = 0;
+	uint8_t indexBuf = 0;
 	uint8_t answer;
 
 	memset(aRxBuffer,0,UART_CMD_BUF_SIZE);
@@ -2009,25 +2010,46 @@
 	{
 		do
 		{
-			if(answerOkay[index] != aRxBuffer[index])
+			if(answerOkay[indexRef] == aRxBuffer[indexBuf])
 			{
-				index = sizeAnswer;
-				result = HAL_ERROR;		/* unexpected answer => there might be characters left in RX que => read and discard all rx bytes */
-				do
-				{
-					answer = HAL_UART_Receive(&UartHandle, (uint8_t*)&aRxBuffer[index], 1, 10);
-					if (index < UART_CMD_BUF_SIZE) 
-					{
-						index++;
-					}
-				}while(answer == HAL_OK);
-				index = sizeAnswer;
+				indexRef++;
 			}
 			else
 			{
-				index++;
+				if(indexRef != 0)
+				{
+					indexRef = 0;
+				}
 			}
-		}while(index < sizeAnswer);
+			indexBuf++;
+		}while(indexBuf < sizeAnswer);
+
+		if(indexRef != sizeAnswer)		/* unexpected answer => there might be characters left in RX que => read and check all rx bytes */
+		{
+			do
+			{
+				answer = HAL_UART_Receive(&UartHandle, (uint8_t*)&aRxBuffer[indexBuf], 1, 10);
+				if (indexBuf < UART_CMD_BUF_SIZE)
+				{
+					if(answerOkay[indexRef] == aRxBuffer[indexBuf])
+					{
+						indexRef++;
+					}
+					else
+					{
+						if(indexRef != 0)
+						{
+							indexRef = 0;
+						}
+					}
+					indexBuf++;
+				}
+			}while(answer == HAL_OK);
+			if(indexRef != sizeAnswer)
+			{
+				result = HAL_ERROR;
+			}
+		}
 	}
 	else
 	{
@@ -2175,14 +2197,8 @@
 		CmdSize = strlen(TxBuffer);
 		if(HAL_UART_Transmit(&UartHandle, (uint8_t*)TxBuffer,CmdSize, 2000) == HAL_OK)
 		{
-			if(BmTmpConfig == BM_CONFIG_ECHO)	/* echo is not yet turned off => read and discard echo */
-			{
-				HAL_UART_Receive(&UartHandle, (uint8_t*)TxBuffer, CmdSize, UART_OPERATION_TIMEOUT);
-			}
-
 			result = tComm_CheckAnswerOK();
 
-
 			if((BmTmpConfig == BM_CONFIG_BAUD) && (result == HAL_OK) && (UartHandle.Init.BaudRate != 460800)) /* is com already switched to fast speed? */
 			{
 				HAL_UART_DeInit(&UartHandle);
@@ -2190,6 +2206,19 @@
 				UartHandle.Init.BaudRate   = 460800;
 				HAL_UART_Init(&UartHandle);
 			}
+			if((BmTmpConfig == BM_CONFIG_BAUD) && (result == HAL_OK) && (UartHandle.Init.BaudRate == 460800)) /* This shut not happen because default speed is 115200 => update module configuration */
+			{
+				sprintf(TxBuffer,"AT%%B8\r");	/* set default baudrate */
+				CmdSize = strlen(TxBuffer);
+				HAL_UART_Transmit(&UartHandle, (uint8_t*)TxBuffer,CmdSize, 2000);
+				HAL_UART_DeInit(&UartHandle);
+				HAL_Delay(10);
+				UartHandle.Init.BaudRate   = 115200;
+				HAL_UART_Init(&UartHandle);
+				sprintf(TxBuffer,"AT&W\r");		/* write configuration */
+				CmdSize = strlen(TxBuffer);
+				HAL_UART_Transmit(&UartHandle, (uint8_t*)TxBuffer,CmdSize, 2000);
+			}
 			if(result == HAL_OK)
 			{
 				BmTmpConfig++;
@@ -2197,6 +2226,7 @@
 			if(BmTmpConfig == BM_CONFIG_DONE)
 			{
 				ConfigRetryCnt = 0;
+				RestartModule = 1;
 			}
 		}
 	}
@@ -2210,6 +2240,14 @@
 			{
 				RestartModule = 0;      /* only one try */
 				ConfigRetryCnt = 200;	/* used for delay to startup module again */
+
+				if(BmTmpConfig == BM_CONFIG_ECHO)	/* the module did not answer even once => try again with alternative baud rate */
+				{
+					HAL_UART_DeInit(&UartHandle);
+					HAL_Delay(1);
+					UartHandle.Init.BaudRate   = 460800;
+					HAL_UART_Init(&UartHandle);
+				}
 				BmTmpConfig = BM_CONFIG_RETRY;
 			}
 			else						/* even restarting module failed => switch bluetooth off */