Tweaked the Atmel ARM7 MS/TP settings.

bacnet-stack/mstp.c

@@ -917,7 +917,7 @@ bool MSTP_Master_Node_FSM(volatile struct mstp_port_struct_t * mstp_port)
         /* The PASS_TOKEN state listens for a successor to begin using */
         /* the token that this node has just attempted to pass. */
     case MSTP_MASTER_STATE_PASS_TOKEN:
-        if (mstp_port->SilenceTimer < Tusage_timeout) {
+        if (mstp_port->SilenceTimer <= Tusage_timeout) {
             if (mstp_port->EventCount > Nmin_octets) {
                 /* SawTokenUser */
                 /* Assume that a frame has been sent by the new token user.  */
@@ -1026,7 +1026,7 @@ bool MSTP_Master_Node_FSM(volatile struct mstp_port_struct_t * mstp_port)
                 transition_now = true;
             }
             mstp_port->ReceivedValidFrame = false;
-        } else if ((mstp_port->SilenceTimer >= Tusage_timeout) ||
+        } else if ((mstp_port->SilenceTimer > Tusage_timeout) ||
             (mstp_port->ReceivedInvalidFrame == true)) {
             if (mstp_port->SoleMaster == true) {
                 /* SoleMaster */

bacnet-stack/mstp.h

@@ -99,13 +99,13 @@ typedef enum {
 /* that a node must wait for a station to begin replying to a */
 /* confirmed request: 255 milliseconds. (Implementations may use */
 /* larger values for this timeout, not to exceed 300 milliseconds.) */
-#define Treply_timeout 255
+#define Treply_timeout 260
 
 /* The minimum time without a DataAvailable or ReceiveError event that a */
 /* node must wait for a remote node to begin using a token or replying to */
 /* a Poll For Master frame: 20 milliseconds. (Implementations may use */
 /* larger values for this timeout, not to exceed 100 milliseconds.) */
-#define Tusage_timeout 20
+#define Tusage_timeout 25
 
 
 struct mstp_port_struct_t {

bacnet-stack/ports/at91sam7s/dlmstp.c

@@ -124,9 +124,12 @@ int dlmstp_send_pdu(BACNET_ADDRESS * dest, /* destination address */
 
 static void dlmstp_task(void)
 {
+    volatile AT91PS_PIO pPIO = AT91C_BASE_PIOA;
     /* only do receive state machine while we don't have a frame */
     if ((MSTP_Port.ReceivedValidFrame == false) &&
         (MSTP_Port.ReceivedInvalidFrame == false)) {
+	/* LED OFF */
+        pPIO->PIO_SODR = LED2;
         do {
             RS485_Check_UART_Data(&MSTP_Port);
             MSTP_Receive_Frame_FSM(&MSTP_Port);
@@ -135,13 +138,8 @@ static void dlmstp_task(void)
                 break;
         } while (MSTP_Port.DataAvailable);
     } else {
-        /* toggle LED on Frame received */
+	/* LED ON */
-        volatile AT91PS_PIO pPIO = AT91C_BASE_PIOA;
-        if  ((pPIO->PIO_ODSR & LED2) == LED2)
         pPIO->PIO_CODR = LED2;
-        else
-            pPIO->PIO_SODR = LED2;
-
     }
     /* only do master state machine while rx is idle */
     if (MSTP_Port.receive_state == MSTP_RECEIVE_STATE_IDLE) {

bacnet-stack/ports/at91sam7s/makefile

@@ -12,7 +12,8 @@ LDSCRIPT=at91sam7s256.ld
 
 BACNET_FLAGS = -DBACDL_MSTP=1 -DPRINT_ENABLED=0 -DBIG_ENDIAN=0 -DMAX_APDU=480 -DDLMSTP_TEST
 INCLUDES = -I. -I../.. -I../../demo/handler -I../../demo/object 
-OPTIMIZATION = -O0
+#OPTIMIZATION = -O0
+OPTIMIZATION = -Os
 CFLAGS = -fno-common $(OPTIMIZATION) $(INCLUDES) $(BACNET_FLAGS) -Wall -g
 #  -Wa,<options> Pass comma-separated <options> on to the assembler
 AFLAGS = -Wa,-ahls,-mapcs-32,-adhlns=$(<:.s=.lst)

bacnet-stack/ports/at91sam7s/rs485.c

@@ -38,7 +38,7 @@
 #include "board.h"
 
 /* UART */
-static AT91S_USART *RS485_Interface = AT91C_BASE_US0;
+static volatile AT91S_USART *RS485_Interface = AT91C_BASE_US0;
 /* baud rate */
 static int RS485_Baud = 38400;
 
@@ -50,7 +50,7 @@ static int RS485_Baud = 38400;
 *****************************************************************************/
 void RS485_Set_Interface(char *ifname)
 {
-    RS485_Interface = (AT91S_USART *)ifname;
+    RS485_Interface = (volatile AT91S_USART *)ifname;
 }
 
 /****************************************************************************
@@ -76,7 +76,7 @@ void RS485_Initialize(void)
         AT91C_US_TXDIS;           /* Transmitter Disable */
 
     RS485_Interface->US_MR =
-        AT91C_US_USMODE_RS485  |  /* RS-485 Mode - RTS auto asserted */
+        AT91C_US_USMODE_RS485  |  /* RS-485 Mode - RTS auto assert */
         AT91C_US_CLKS_CLOCK    |  /* Clock = MCK */
         AT91C_US_CHRL_8_BITS   |  /* 8-bit Data  */
         AT91C_US_PAR_NONE      |  /* No Parity   */
@@ -146,31 +146,25 @@ void RS485_Send_Frame(
     uint16_t nbytes)   /* number of bytes of data (up to 501) */
 {
     uint8_t turnaround_time;
-    uint32_t baud;
 
     /* toggle LED on send */
     volatile AT91PS_PIO pPIO = AT91C_BASE_PIOA;
-    if  ((pPIO->PIO_ODSR & LED1) == LED1)
+    /* LED ON */
     pPIO->PIO_CODR = LED1;
-    else
-        pPIO->PIO_SODR = LED1;
     /* delay after reception - per MS/TP spec */
     if (mstp_port) {
-        baud = RS485_Get_Baud_Rate();
         /* wait about 40 bit times since reception */
-        if (baud == 9600)
+        turnaround_time = (40*1000)/RS485_Baud;
-            turnaround_time = 4;
+        if (!turnaround_time) {
-        else if (baud == 19200)
-            turnaround_time = 2;
-        else
             turnaround_time = 1;
+        }
         while (mstp_port->SilenceTimer < turnaround_time) {
             /* do nothing - wait for timer to increment */
         };
     }
     while (nbytes) {
         while (!(RS485_Interface->US_CSR & AT91C_US_TXRDY)) {
-            /* do nothing - wait for Tx buffer to get empty */
+            /* do nothing - wait until Tx buffer is empty */
         }
         RS485_Interface->US_THR = *buffer;
         buffer++;
@@ -180,6 +174,11 @@ void RS485_Send_Frame(
             mstp_port->SilenceTimer = 0;
         }
     }
+    while (!(RS485_Interface->US_CSR & AT91C_US_TXRDY)) {
+        /* do nothing - wait until Tx buffer is empty */
+    }
+    /* LED OFF */
+    pPIO->PIO_SODR = LED1;
 
     return;
 }

bacnet-stack/ports/at91sam7s/timer.c

@@ -2,7 +2,7 @@
 //
 //     Purpose:  Set up the 16-bit Timer/Counter
 //
-//     We will use Timer Channel 0 to develop a 50 msec interrupt.
+//     We will use Timer Channel 0 to develop a 1 msec interrupt.
 //
 //     The AT91SAM7S-EK board has a 18,432,000 hz crystal oscillator.
 //
@@ -16,9 +16,9 @@
 //
 //     TIMER_CLOCK5 Period = 1 / 46928  =  21.309239686 microseconds
 //
-//     A little algebra:  .050 sec = count * 21.3092396896*10**-6
+//     A little algebra:  .001 sec = count * 21.3092396896*10**-6
-//                        count =  .050 / 21.3092396896*10**-6
+//                        count =  .001 / 21.3092396896*10**-6
-//                        count =  2346
+//                        count =  46.928
 //
 //
 //     Therefore:  set Timer Channel 0 register RC to 9835
@@ -31,6 +31,9 @@
 //                 disable all the other timer 0 interrupts
 //
 // Author:  James P Lynch  May 12, 2007
+// Modified by Steve Karg
+//     Changed timer to 1ms.
+//     Encapsulated the intialization
 // *****************************************************************************
 
 
@@ -43,8 +46,7 @@
 // global variable counts interrupts
 volatile unsigned long Timer_Milliseconds = 0;
 
-void	TimerSetup(void) {
+void Timer0_Setup(int milliseconds) {
-	
     //        TC Block Control Register TC_BCR    (read/write)
     //
     //    |------------------------------------------------------------------|------|
@@ -198,8 +200,11 @@ void	TimerSetup(void) {
     //                        count =  .001 / 21.3092396896*10**-6
     //                        count =  46.928
     //
-	pTC->TC_RC = 47;										
+    //    STK: Even Simpler, let the compiler do the work:
-
+    //
+    //    TIMER_CLOCK5 = (MCK / 1024) / 1000
+    //                 = 48054841 / 1024 / 1000 =  46.928
+    pTC->TC_RC = ((MCK/1024/1000)+1)*milliseconds;
 
     //        TC Interrupt Enable Register  TC_IER    (write-only)
     //
@@ -235,7 +240,6 @@ void	TimerSetup(void) {
     //
     pTC->TC_IER = 0x10;                // enable RC compare interrupt
 
-
     //        TC Interrupt Disable Register  TC_IDR    (write-only)
     //
     //
@@ -275,36 +279,49 @@ void	TimerSetup(void) {
 //
 //     Timer 0 Interrupt Service Routine
 //
-//	   entered when Timer0 RC compare interrupt asserts (200 msec period)
+//     Entered when Timer0 RC compare interrupt asserts
-//     blinks LED2 (pin PA2)
 //
 //  Author:  James P Lynch  May 12, 2007
+//  Modified by Steve Karg
+//    simplified and changed to a millisecond count-up timer
 //  *****************************************************************************
 void Timer0IrqHandler (void) {
 
     volatile AT91PS_TC pTC = AT91C_BASE_TC0; // pointer to timer channel 0 register structure
     unsigned int dummy; // temporary
 
-	dummy = pTC->TC_SR;									// read TC0 Status Register to clear interrupt	
+    // read TC0 Status Register to clear interrupt
-	Timer_Milliseconds++;										// increment the tick count
+    dummy = pTC->TC_SR;
+    // increment the tick count
+    Timer_Milliseconds++;
 }
 
 void TimerInit(void) {
-
     // enable the Timer0 peripheral clock
     volatile AT91PS_PMC    pPMC = AT91C_BASE_PMC;
     pPMC->PMC_PCER = pPMC->PMC_PCSR | (1<<AT91C_ID_TC0);
     // Set up the AIC  registers for Timer 0
-    volatile AT91PS_AIC	pAIC = AT91C_BASE_AIC;			// pointer to AIC data structure
+    volatile AT91PS_AIC    pAIC = AT91C_BASE_AIC;
-    pAIC->AIC_IDCR = (1<<AT91C_ID_TC0);					// Disable timer 0 interrupt in AIC Interrupt Disable Command Register			
+    // Disable timer 0 interrupt
-    pAIC->AIC_SVR[AT91C_ID_TC0] =						// Set the TC0 IRQ handler address in AIC Source 
+    // in AIC Interrupt Disable Command Register
-        (unsigned int)Timer0IrqHandler;        			// Vector Register[12]
+    pAIC->AIC_IDCR = (1<<AT91C_ID_TC0);
-    pAIC->AIC_SMR[AT91C_ID_TC0] =						// Set the interrupt source type and priority 
+    // Set the TC0 IRQ handler address in
-        (AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE | 0x4 ); 		// in AIC Source Mode Register[12]
+    // AIC Source Vector Register[12]
-    pAIC->AIC_ICCR = (1<<AT91C_ID_TC0); 				// Clear the TC0 interrupt in AIC Interrupt Clear Command Register
+    pAIC->AIC_SVR[AT91C_ID_TC0] =
-    pAIC->AIC_IDCR = (0<<AT91C_ID_TC0);					// Remove disable timer 0 interrupt in AIC Interrupt Disable Command Reg			
+        (unsigned int)Timer0IrqHandler;
-    pAIC->AIC_IECR = (1<<AT91C_ID_TC0); 				// Enable the TC0 interrupt in AIC Interrupt Enable Command Register
+    // Set the interrupt source type and priority
-    
+    // in AIC Source Mode Register[12]
-    // Setup timer0 to generate a 10 msec periodic interrupt
+    pAIC->AIC_SMR[AT91C_ID_TC0] =
-    TimerSetup();  
+        (AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE | 0x4 );
+    // Clear the TC0 interrupt 
+    // in AIC Interrupt Clear Command Register
+    pAIC->AIC_ICCR = (1<<AT91C_ID_TC0);
+    // Remove disable timer 0 interrupt 
+    // in AIC Interrupt Disable Command Reg
+    pAIC->AIC_IDCR = (0<<AT91C_ID_TC0);
+    // Enable the TC0 interrupt 
+    // in AIC Interrupt Enable Command Register
+    pAIC->AIC_IECR = (1<<AT91C_ID_TC0);
+    // Setup timer0 to generate a 1 msec periodic interrupt
+    Timer0_Setup(1);
 }