/******************************************************************************
*
* Controller Area Network (CAN) Demo-Application
* Atmel AVR with Microchip MCP2515
*
* Copyright (C) 2005 Martin THOMAS, Kaiserslautern, Germany
* <eversmith@heizung-thomas.de>
* http://www.siwawi.arubi.uni-kl.de/avr_projects
*
*****************************************************************************
*
* File : main.c
* Version : 0.9
*
* Summary : Application Entry
* Test-Platform: Atmel ATmega + Microchip MCP2515
* Here the MCP2515 is clocked by the AVR (see clock_init()).
*
* This application uses Peter Fleury's free AVR-U(S)ART library which
* has been slightly extended. See comments in uart.c.
*
*****************************************************************************/
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/wdt.h>
#include <avr/eeprom.h>
#include "uart.h"
#include "spi.h"
#include "can.h"
#include "delay.h"
#include "termio.h"
#include "terminal.h"
#include "gpio.h"
#include "timebase.h"
#include "debughelper.h"
#define VERBOSE (1)
#define OSCAL_READEEPROM (1)
#if defined(__AVR_ATmega8__) || defined(__AVR_ATmega16__)
#define OSCAL_EEPROMADDR ((void*)0x1ff)
#elif defined(__AVR_ATmega32__)
#define OSCAL_EEPROMADDR ((void*)0x3ff)
#else
#error "eeprom addr. undefined for this target"
#endif
#define OSCAL_VALUE (0xA5)
#define BAUD 19200
#define AUTOSENDPORT PORTD
#define AUTOSENDDDR DDRD
#define AUTOSENDPIN PIND
#define AUTOSENDBIT PD7
#if 0
void clock_init_tc2(void)
// to clock the MCP2515
// - CTC Mode of Timer-Counter 2
// - Freq at OC2 (datasheet): f=f_c/(2*N*(1+OCR2))
// with: f_c=system clock=8MHz, N=prescaler=1, OCR2=0 -> 4MHz @ Pin D7
{
// set OC2-Pin (PD7 on ATmega16) as output
DDRD |= _BV(DDD7);
// CTC limit in OCR2
OCR2=0;
// Clear Timer on Compare Match (CTC) mode; toogle OC2(PD7) on compare match;
// clock select (timer2 prescaler) to clk/1 (no prescaling CS20=1)
TCCR2=_BV(WGM21)|_BV(COM20)|_BV(CS20);
}
#endif
void clock_init_tc1a(void)
// to clock the MCP2515 on Mega8/Mega32
// - CTC Mode of Timer-Counter 1 use OC1A as clock-pin
// - Freq at OC2 (datasheet): f=f_c/(2*N*(1+OCR2))
// with: f_c=system clock=8MHz, N=prescaler=1, OCR1A=0 -> 4MHz
// @ Pin B1 Mega8
// @ Pin D5 Mega32
{
#if defined(__AVR_ATmega8__)
// set OC2-Pin (PB1 on ATmega8) as output
DDRB |= _BV(DDB1);
#elif defined(__AVR_ATmega32__) || defined(__AVR_ATmega16__)
// set OC2-Pin (PD5 on ATmega32) as output
DDRD |= _BV(DDD5);
#else
#error "OCR1A pin undefined for this target"
#endif
// CTC limit in OCR1A
OCR1A=0;
// Clear Timer on Compare Match (CTC) mode; toogle OC1A(PB1) on compare match;
TCCR1A=_BV(COM1A0);
// clock select (timer2 prescaler)
TCCR1B=_BV(CS10)|_BV(WGM12); // to clk/1 (no prescaling CS10=1)
}
static void process_CANMessages(void)
{
CanMessage msg;
uint8_t data2;
#ifdef VERBOSE
term_puts_P("AutoProcessing\n");
#endif
while ( can_readMessage(&msg) == CAN_OK ) {
data2 = msg.dta[2];
if ( data2<3 ) {
gpio_toggle_led( (1<<data2) );
#ifdef VERBOSE
Debug_ByteToUart_P("data2",data2);
#endif
}
}
}
int main(void)
{
uint8_t res, flag;
uint8_t shellstate;
uint16_t timebuf;
#if OSCAL_READEEPROM
res = eeprom_read_byte(OSCAL_EEPROMADDR);
if (res != 0xff) OSCCAL = res;
else OSCCAL = OSCAL_VALUE; // take default from define
#else
OSCCAL = OSCAL_VALUE;
#endif
gpio_init();
gpio_set_led(LED1);
timebase_init();
uart_init((UART_BAUD_SELECT((BAUD),F_OSC)));
sei();
term_puts_P( "\n\nMCP2515 Interface Demo (c) Martin Thomas\n" );
Debug_ByteToUart_P("OSCCAL", OSCCAL);
term_puts_P("\nSetting up MCP clock to FOSC/2\n");
clock_init_tc1a(); // init MCP2515 clock-source (=AVR FOSC/2)
// old: clock_init(); */
term_puts_P("SPI init\n");
spi_init(); // init SPI-Interface (as "Master")
term_puts_P("CAN init ");
// res = can_init(CAN_125KBPS);
res = can_init(CAN_20KBPS);
if (res == CAN_OK) term_puts_P("- OK\n");
else term_puts_P("- FAIL\n");
term_puts_P("Autosend (\"Autosendbit\"-State) : ");
AUTOSENDDDR &= ~(1<<AUTOSENDBIT); // as input
AUTOSENDPORT |= (1<<AUTOSENDBIT); // int pullup on
if ( AUTOSENDPIN & (1<<AUTOSENDBIT) ) {
gTimedSend = CANAUTOOFF;
term_puts_P("off");
}
else {
gTimedSend = CANAUTOON;
term_puts_P("on");
}
term_puts_P("\n");
can_debug1();
shellstate = COMMANDSHELL_MODEINIT;
flag = 0;
timebuf = timebase_actTime();
#if 0
for (;;) {
if (timebase_passedTimeMS(timebuf)>=1000) {
timebuf = timebase_actTime();
term_puts_P("(.)");
}
}
#endif
for (;;) {
CommandShell(&shellstate);
if ( shellstate == COMMANDSHELL_MODEEXIT ) {
term_puts_P("I have no operation system to exit to :-( -> WD-Reset");
wdt_enable ( WDTO_500MS );
while(1);
}
if ( ( can_checkReceive() == CAN_MSGAVAIL ) ) {
if (!flag) {
#ifdef VERBOSE
term_puts_P("\nAt least one CAN-Message available!\n");
shellstate = COMMANDSHELL_REDRAW;
#endif
flag = 1;
}
if ( gCANAutoProcess == CANAUTOON ) {
process_CANMessages();
#ifdef VERBOSE
shellstate = COMMANDSHELL_REDRAW;
#endif
}
}
else {
flag = 0;
}
if (timebase_passedTimeMS(timebuf)>=1000) {
timebuf = timebase_actTime();
if (gTimedSend == CANAUTOON) {
if ( can_testTransmit(CAN_STDID, 1) != CAN_OK ) {
term_puts_P("\nAuto-Transmit (debug) failed\n");
can_dumpStatus();
shellstate = COMMANDSHELL_REDRAW;
}
}
if ( can_checkError() != CAN_OK ) {
can_dumpStatus();
}
}
// else term_puts_P("Checking\n");
}
return 0;
}