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/******************************************************************************

 *

 * 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;

}