can5.c

//*****************************************************************************
// Author               : Nicolas Weber
// Created              : 14.05.2010
// Target MCU   : Fujitsu MB96300 series
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
//*****************************************************************************

#include "can3.h"
#include "can4.h"
#include "can5.h"
#include "../util.h"
#include "mb96348hs.h"

#define CAN5_PING_MSG uint8_t data[4]; data[0] = 'P'; data[1] = 'I'; data[2] = 'N'; data[3] = 'G';
#define CAN5_PING_ANS uint8_t data[4]; data[0] = 'P'; data[1] = 'A'; data[2] = 'N'; data[3] = 'S';

uint32_t pings[2];      //64 max addresses

static uint8_t can5_internal_ping(uint8_t address);
static void can5_irqHandler(void);

uint8_t can5_init(void) {
        if(can4_init(CAN3_MAX_ADDRESS) && can4_open(CAN5_PORT) && can3_registerIRQHandler(&can5_irqHandler) && can5_getNewAddress()) {
                return 1;
        }

        return 0;
}

static uint8_t can5_internal_ping(uint8_t address) {
        uint8_t i;
        CAN5_PING_MSG

        //Clear all ping results
        for(i = 0; i < 2; i++)
                pings[i] = 0;

        return can4_send(address,CAN5_PORT,data,4,0);
}

uint8_t can5_isAlive(uint8_t address) {
        uint16_t timeout = 0;
        
        if(address > 63) return 0;

        //ping
        if(!can5_internal_ping(address)) return 0;

        //wait for answer
        while(((address < 32 ? pings[0] & _BV(address) : pings[1] & _BV(address-32)) == 0) || (timeout++ < CAN5_ALIVE_TIMEOUT))
                delay_us(1);

        //timeout
        if(timeout >= CAN5_ALIVE_TIMEOUT) return 0;

        return 1;
}

uint8_t can5_getNewAddress(void) {
        uint16_t timeout = 0;
        uint8_t i;
        uint8_t check;

        //ping
        if(!can5_internal_ping(CAN3_MULTICAST)) return 0;

        //wait for answers
        delay_us(CAN5_PING_TIMEOUT);

        //get free address
        for(i = 0; i < 64; i++) {
                if(i < 32)              check = pings[0] & _BV(i);
                else                    check = pings[1] & _BV(i-32);

                if(check == 0) {
                        can3_setAddress(i);
                        return 1;
                }
        }

        //all addresses used
        return 0;
}

static void can5_irqHandler(void) {
        uint8_t recdata[4];
        uint8_t src;
        uint8_t len;

        len = can4_getData(CAN5_PORT,recdata,&src);

        if(len > 0) {
                if(recdata[0] == 'P' && recdata[1] == 'I' && recdata[2] == 'N' && recdata[3] == 'G') {
                        CAN5_PING_ANS
                        can4_send(src,CAN5_PORT,data,4,0);
                } else if(recdata[0] == 'P' && recdata[1] == 'A' && recdata[2] == 'N' && recdata[3] == 'S') {
                        if(src < 32)    pings[0] |= _BV(src);
                        else                    pings[1] |= _BV(src-32);
                }
        }
}

void can5_close(void) {
        can3_removeIRQHandler(&can5_irqHandler);
        can4_close(CAN5_PORT);
}