Converted SilenceTimer on MS/TP datalink to be a function so that it can be atomic on 8-bit microcontrollers.

bacnet-stack/ports/at91sam7s/dlmstp.c

@@ -33,6 +33,7 @@
 #include "npdu.h"
 /* This file has been customized for use with the AT91SAM7S-EK */
 #include "board.h"
+#include "timer.h"
 
 /* Number of MS/TP Packets Rx/Tx */
 uint16_t MSTP_Packets = 0;
@@ -46,13 +47,6 @@ static volatile struct mstp_port_struct_t MSTP_Port;
 static uint8_t TxBuffer[MAX_MPDU];
 static uint8_t RxBuffer[MAX_MPDU];
 
-#define INCREMENT_AND_LIMIT_UINT16(x) {if (x < 0xFFFF) x++;}
-
-volatile uint16_t *dlmstp_millisecond_timer_address(void)
-{
-    return &(MSTP_Port.SilenceTimer);
-}
-
 void dlmstp_copy_bacnet_address(BACNET_ADDRESS * dest, BACNET_ADDRESS * src)
 {
     int i = 0;
@@ -83,8 +77,10 @@ bool dlmstp_init(char *ifname)
     MSTP_Port.InputBufferSize = sizeof(RxBuffer);
     MSTP_Port.OutputBuffer = &TxBuffer[0];
     MSTP_Port.OutputBufferSize = sizeof(TxBuffer);
+    MSTP_Init.SilenceTimer = Timer_Silence;
+    MSTP_Init.SilenceTimerReset = Timer_Silence_Reset;
     MSTP_Init(&MSTP_Port);
-    
+
     return true;
 }
 

bacnet-stack/ports/at91sam7s/timer.c

@@ -45,11 +45,12 @@
 #include "board.h"
 #include "dlmstp.h"
 
-// global variable counts interrupts
+/* global variable counts interrupts */
 volatile unsigned long Timer_Milliseconds;
-volatile uint16_t *pTimer_MSTP_Silence;
+/* MS/TP Silence Timer */
+static volatile uint16_t SilenceTime;
 
-void Timer0_Setup(int milliseconds) {
+static void Timer0_Setup(int milliseconds) {
     //        TC Block Control Register TC_BCR    (read/write)
     //
     //    |------------------------------------------------------------------|------|
@@ -296,7 +297,7 @@ void Timer0_Setup(int milliseconds) {
 //  Modified by Steve Karg
 //    simplified and changed to a millisecond count-up timer
 //  *****************************************************************************
-void Timer0IrqHandler (void) {
+static void Timer0IrqHandler (void) {
 
     volatile AT91PS_TC pTC = AT91C_BASE_TC0; // pointer to timer channel 0 register structure
     unsigned int dummy; // temporary
@@ -305,10 +306,21 @@ void Timer0IrqHandler (void) {
     dummy = pTC->TC_SR;
     // increment the tick count
     Timer_Milliseconds++;
-    if ((*pTimer_MSTP_Silence) < 0xFFFF)
-        (*pTimer_MSTP_Silence)++;
+    if (SilenceTime < 0xFFFF)
+        SilenceTime++;
 }
 
+uint16_t Timer_Silence(void)
+{
+    return SilenceTime;
+}
+
+void Timer_Silence_Reset(void)
+{
+    SilenceTime = 0;
+}
+
+
 //  *****************************************************************************
 //
 //     Timer 0 Initialization

bacnet-stack/ports/at91sam7s/timer.h

@@ -0,0 +1,44 @@
+/**************************************************************************
+*
+* Copyright (C) 2007 Steve Karg <skarg@users.sourceforge.net>
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be included
+* in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*
+*********************************************************************/
+
+#ifndef TIMER_H
+#define TIMER_H
+
+#include <stdint.h>
+
+extern volatile unsigned long Timer_Milliseconds;
+
+#ifdef __cplusplus
+extern "C" {
+#endif                          /* __cplusplus */
+
+    void TimerInit(void);
+    uint16_t Timer_Silence(void);
+    void Timer_Silence_Reset(void);
+
+#ifdef __cplusplus
+}
+#endif                          /* __cplusplus */
+#endif