Index: firmware/App/Drivers/SafetyShutdown.c
===================================================================
diff -u -rb64c49fdcf2b6d95e61e63f8e258c4e600935bbd -ref5ef16518466c92687b869cabfa16eaf3365dc0
--- firmware/App/Drivers/SafetyShutdown.c	(.../SafetyShutdown.c)	(revision b64c49fdcf2b6d95e61e63f8e258c4e600935bbd)
+++ firmware/App/Drivers/SafetyShutdown.c	(.../SafetyShutdown.c)	(revision ef5ef16518466c92687b869cabfa16eaf3365dc0)
@@ -1,57 +1,54 @@
-/**************************************************************************
- *
- *  Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
- *
- *  THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
- *  WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
- *
- *  @file SafetyShutdown.c
- *
- *  @date 20-Sep-2019
- *  @author S. Nash
- *
- *  @brief Controller for the safety shutdown signal.
- *
- **************************************************************************/
-
-#include "gio.h"
-
-#include "SafetyShutdown.h"
-
-// ********** private definitions **********
-
-// GIO port A pin assignments for pins connected to CPLD
-#define SAFETY_GIO_PORT_PIN         3U
-
-// CPLD pin I/O macros
-#define SET_SAFETY_SHUTDOWN()       gioSetBit( gioPORTB, SAFETY_GIO_PORT_PIN, PIN_SIGNAL_HIGH )
-#define CLR_SAFETY_SHUTDOWN()       gioSetBit( gioPORTB, SAFETY_GIO_PORT_PIN, PIN_SIGNAL_LOW )
-
-/*************************************************************************
- * @brief initSafetyShutdown
- * The initSafetyShutdown function initializes the Buttons module.
- * @details
- * Inputs : none
- * Outputs : Safety Shutdown module signal output set to initial state.
- * @param none
- * @return none
- *************************************************************************/
-void initSafetyShutdown( void )
-{
-    CLR_SAFETY_SHUTDOWN();
-}
-
-/*************************************************************************
- * @brief activateSafetyShutdown
- * The activateSafetyShutdown function activates the safety shutdown signal.
- * @details
- * Inputs : none
- * Outputs : Safety Shutdown signal output set to active state.
- * @param none
- * @return none
- *************************************************************************/
-void activateSafetyShutdown( void )
-{
-    SET_SAFETY_SHUTDOWN();
-}
-
+/**************************************************************************
+ *
+ *  Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
+ *
+ *  THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
+ *  WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
+ *
+ *  @file SafetyShutdown.c
+ *
+ *  @date 20-Sep-2019
+ *  @author S. Nash
+ *
+ *  @brief Controller for the safety shutdown signal.
+ *
+ **************************************************************************/
+
+#include "mibspi.h"
+
+#include "SafetyShutdown.h"
+
+// ********** private definitions **********
+
+// pin I/O macros
+#define SAFETY_SPI1_PORT_MASK       0x00000010  // (CS[4] - re-purposed as output GPIO)
+#define SET_SAFETY_SHUTDOWN()       {mibspiREG1->PC3 |= SAFETY_SPI1_PORT_MASK;}
+#define CLR_SAFETY_SHUTDOWN()       {mibspiREG1->PC3 &= ~SAFETY_SPI1_PORT_MASK;}
+
+/*************************************************************************
+ * @brief initSafetyShutdown
+ * The initSafetyShutdown function initializes the Buttons module.
+ * @details
+ * Inputs : none
+ * Outputs : Safety Shutdown module signal output set to initial state.
+ * @param none
+ * @return none
+ *************************************************************************/
+void initSafetyShutdown( void )
+{
+    CLR_SAFETY_SHUTDOWN();
+}
+
+/*************************************************************************
+ * @brief activateSafetyShutdown
+ * The activateSafetyShutdown function activates the safety shutdown signal.
+ * @details
+ * Inputs : none
+ * Outputs : Safety Shutdown signal output set to active state.
+ * @param none
+ * @return none
+ *************************************************************************/
+void activateSafetyShutdown( void )
+{
+    SET_SAFETY_SHUTDOWN();
+}