diff --git a/os/hal/include/hal_sio.h b/os/hal/include/hal_sio.h
index 38de473bd..c1f36f939 100644
--- a/os/hal/include/hal_sio.h
+++ b/os/hal/include/hal_sio.h
@@ -59,19 +59,21 @@
  * @name    SIO configuration options
  * @{
  */
+/**
+ * @brief   Default bit rate.
+ * @details Configuration parameter, this is the baud rate selected for the
+ *          default configuration.
+ */
+#if !defined(SIO_DEFAULT_BITRATE) || defined(__DOXYGEN__)
+#define SIO_DEFAULT_BITRATE                 38400
+#endif
+
 /**
  * @brief   Support for thread synchronization API.
  */
 #if !defined(HAL_SIO_USE_SYNCHRONIZATION) || defined(__DOXYGEN__)
 #define HAL_SIO_USE_SYNCHRONIZATION         TRUE
 #endif
-
-/**
- * @brief   Support for callbacks.
- */
-#if !defined(HAL_SIO_USE_CALLBACKS) || defined(__DOXYGEN__)
-#define HAL_SIO_USE_CALLBACKS               TRUE
-#endif
 /** @} */
 
 /*===========================================================================*/
diff --git a/os/hal/ports/STM32/LLD/USARTv2/hal_sio_lld.c b/os/hal/ports/STM32/LLD/USARTv2/hal_sio_lld.c
index e459c147d..959c0dfcb 100644
--- a/os/hal/ports/STM32/LLD/USARTv2/hal_sio_lld.c
+++ b/os/hal/ports/STM32/LLD/USARTv2/hal_sio_lld.c
@@ -123,6 +123,19 @@ SIODriver LPSIOD1;
 /* Driver local variables and types.                                         */
 /*===========================================================================*/
 
+/**
+ * @brief   Driver default configuration.
+ * @note    In this implementation it is: 38400-8-N-1, RX and TX FIFO
+ *          thresholds set to 50%.
+ */
+static const SIOConfig default_config = {
+  .baud  = SIO_DEFAULT_BITRATE,
+  .presc = USART_PRESC1,
+  .cr1   = USART_CR1_DATA8 | USART_CR1_OVER16,
+  .cr2   = USART_CR2_STOP1_BITS,
+  .cr3   = USART_CR3_TXFTCFG_1H | USART_CR3_RXFTCFG_1H
+};
+
 /*===========================================================================*/
 /* Driver local functions.                                                   */
 /*===========================================================================*/
@@ -299,6 +312,12 @@ void sio_lld_init(void) {
  */
 bool sio_lld_start(SIODriver *siop) {
 
+  /* Using the default configuration if the application passed a
+     NULL pointer.*/
+  if (siop->config == NULL) {
+    siop->config = &default_config;
+  }
+
   if (siop->state == SIO_STOP) {
 
   /* Enables the peripheral.*/
diff --git a/os/hal/src/hal_sio.c b/os/hal/src/hal_sio.c
index 19bac54a2..3a37b9f3d 100644
--- a/os/hal/src/hal_sio.c
+++ b/os/hal/src/hal_sio.c
@@ -38,6 +38,14 @@
 /* Driver local variables and types.                                         */
 /*===========================================================================*/
 
+static const SIOOperation default_operation = {
+  .rx_cb      = NULL,
+  .rx_idle_cb = NULL,
+  .tx_cb      = NULL,
+  .tx_end_cb  = NULL,
+  .rx_evt_cb  = NULL
+};
+
 /*===========================================================================*/
 /* Driver local functions.                                                   */
 /*===========================================================================*/
@@ -108,7 +116,7 @@ static msg_t __put(void *ip, uint8_t b) {
 
   msg = sioSynchronizeTX(siop, TIME_INFINITE);
   if (msg != MSG_OK) {
-    return MSG_RESET;
+    return msg;
   }
 
   sioPutX(siop, b);
@@ -121,7 +129,7 @@ static msg_t __get(void *ip) {
 
   msg = sioSynchronizeRX(siop, TIME_INFINITE);
   if (msg != MSG_OK) {
-    return MSG_RESET;
+    return msg;
   }
 
   return sioGetX(siop);
@@ -231,7 +239,8 @@ void sioObjectInit(SIODriver *siop) {
  * @brief   Configures and activates the SIO peripheral.
  *
  * @param[in] siop      pointer to the @p SIODriver object
- * @param[in] config    pointer to the @p SIOConfig object
+ * @param[in] config    pointer to the @p SIOConfig object, can be @p NULL
+ *                      if the default configuration is desired
  * @return              The operation status.
  * @retval false        if the driver has been correctly started.
  * @retval true         if an error occurred.
@@ -241,7 +250,7 @@ void sioObjectInit(SIODriver *siop) {
 bool sioStart(SIODriver *siop, const SIOConfig *config) {
   bool result;
 
-  osalDbgCheck((siop != NULL) && (config != NULL));
+  osalDbgCheck(siop != NULL);
 
   osalSysLock();
 
@@ -284,20 +293,28 @@ void sioStop(SIODriver *siop) {
  * @brief   Starts a SIO operation.
  *
  * @param[in] siop          pointer to an @p SIODriver structure
- * @param[in] operation     pointer to an @p SIOOperation structure
+ * @param[in] operation     pointer to an @p SIOOperation structure, can
+ *                          be @p NULL if callbacks are not required
  *                          encoding the operation to be performed
  *
  * @api
  */
 void sioStartOperation(SIODriver *siop, const SIOOperation *operation) {
 
-  osalDbgCheck((siop != NULL) && (operation != NULL));
+  osalDbgCheck(siop != NULL);
 
   osalSysLock();
 
   osalDbgAssert(siop->state == SIO_READY, "invalid state");
 
-  siop->operation = operation;
+  /* The application can pass NULL if it is not interested in callbacks,
+     attaching a default operation structure.*/
+  if (operation != NULL) {
+    siop->operation = operation;
+  }
+  else {
+    siop->operation = &default_operation;
+  }
   siop->state     = SIO_ACTIVE;
 
   sio_lld_start_operation(siop);