Added config option for stdio baud rate

hal/common/retarget.cpp

@@ -98,6 +98,9 @@ static void init_serial() {
 #if DEVICE_SERIAL
     if (stdio_uart_inited) return;
     serial_init(&stdio_uart, STDIO_UART_TX, STDIO_UART_RX);
+#if MBED_CONF_CORE_STDIO_BAUD_RATE
+    serial_baud(&stdio_uart, MBED_CONF_CORE_STDIO_BAUD_RATE);
+#endif
 #endif
 }
 

mbed_lib.json

@@ -4,6 +4,11 @@
         "stdio-convert-newlines": {
             "help": "Enable conversion to standard newlines on stdin/stdout",
             "value": false
+        },
+
+        "stdio-baud-rate": {
+            "help": "Baud rate for stdio",
+            "value": 9600
         }
     }
 }