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Tweaked the Atmel ARM7 MS/TP settings.

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This commit is contained in:
skarg
2007-08-09 23:53:18 +00:00
parent ed5562126e
commit f1deb0b1fe
6 changed files with 301 additions and 286 deletions
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bacnet-stack/ports/at91sam7s/rs485.c
+21 -22
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@@ -33,12 +33,12 @@
#include <stdio.h>
#include "mstp.h"
/* This file has been customized for use with UART0
/* This file has been customized for use with UART0
on the AT91SAM7S-EK */
#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;
}
/****************************************************************************
@@ -63,32 +63,32 @@ void RS485_Set_Interface(char *ifname)
void RS485_Initialize(void)
{
// enable the USART0 peripheral clock
volatile AT91PS_PMC pPMC = AT91C_BASE_PMC;
volatile AT91PS_PMC pPMC = AT91C_BASE_PMC;
pPMC->PMC_PCER = pPMC->PMC_PCSR | (1<<AT91C_ID_US0);
/* enable the peripheral by disabling the pin in the PIO controller */
*AT91C_PIOA_PDR = AT91C_PA5_RXD0 | AT91C_PA6_TXD0 | AT91C_PA7_RTS0;
RS485_Interface->US_CR =
RS485_Interface->US_CR =
AT91C_US_RSTRX | /* Reset Receiver */
AT91C_US_RSTTX | /* Reset Transmitter */
AT91C_US_RXDIS | /* Receiver Disable */
AT91C_US_TXDIS; /* Transmitter Disable */
RS485_Interface->US_MR =
AT91C_US_USMODE_RS485 | /* RS-485 Mode - RTS auto asserted */
RS485_Interface->US_MR =
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 */
AT91C_US_NBSTOP_1_BIT; /* 1 Stop Bit */
/* set the Time Guard to release RTS after x bit times */
RS485_Interface->US_TTGR = 4;
/* baud rate */
RS485_Interface->US_BRGR = MCK/16/RS485_Baud;
RS485_Interface->US_CR =
RS485_Interface->US_CR =
AT91C_US_RXEN | /* Receiver Enable */
AT91C_US_TXEN; /* Transmitter Enable */
@@ -146,32 +146,26 @@ 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)
pPIO->PIO_CODR = LED1;
else
pPIO->PIO_SODR = LED1;
/* LED ON */
pPIO->PIO_CODR = 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 = 4;
else if (baud == 19200)
turnaround_time = 2;
else
turnaround_time = (40*1000)/RS485_Baud;
if (!turnaround_time) {
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++;
nbytes--;
@@ -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;
}