File content as of revision 2:6d4c7f841a5d:

/* 
 * Master device LIN communication library for mbed
 *
 * Copyright (C) 2014 TASS Belgium NV
 * 
 * Released under GPL v2
 *
 * Other licensing models might apply at the sole discretion of the copyright holders.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
 * and associated documentation files (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 
#include "LinMaster.h"

LinMaster::LinMaster(PinName Pin)
{
    DriverStat   = INIT;
    FrameStat    = READY;
    MyPin        = Pin;
    u8BreakLen   = 20;
    u8DelimLen   = 4;
    (void)Baudrate(9600);
}

LinMaster::~LinMaster()
{
    
}

bool LinMaster::Init(void)
{
    DigitalInOut LinPin(MyPin);
    LinPin.output();
    LinPin.write(1);
    
    DriverStat = IDLE;
    
    return ( true );
}

bool LinMaster::Baudrate(uint16_t uBaud)
{
    bool blReturn = false;
    
    if ((uBaud > 0) && (uBaud <= 20000))
    {
        u16BitPeriod = 1000000/uBaud;
        blReturn = true;
    }
    
    return ( blReturn );
}

uint16_t LinMaster::Baudrate(void)
{
    return ( 1000000/u16BitPeriod );
}

bool LinMaster::SendFrame(FrameDir Dir, uint8_t u8ID, uint8_t* ptrData, uint8_t u8Len)
{
    bool blReturn = false;
    uint8_t i;
    
    if (DriverStat == IDLE)
    {
        DriverStat   = TRANSMIT;
        FrameStat    = BREAK;
        u8NextBusLvl = 0;
        u8TickCnt    = 0;
        Direction    = Dir;
        u8FrameID    = u8ID;
        u8FrameLen   = u8Len;
        
        for (i=0; i<u8Len; i++)
        {
            u8FrameData[i]  = *ptrData++;
        }
        
        DigitalInOut LinPin(MyPin);        
        LinPin.output();
        LinPin.write(1);
        
        MyTicker.attach_us(this, &LinMaster::TickEventHndl, u16BitPeriod);
        
        blReturn = true;
    }
    
    return ( blReturn );
}

void LinMaster::TickEventHndl(void)
{
    DigitalInOut LinPin(MyPin);        
    bool blByteSend = false;
    
    if (u8NextBusLvl != 0)
    {
        LinPin.output();
        LinPin.write(1);
    }
    else
    {
        LinPin.output();
        LinPin.write(0);
    }
    
    u8TickCnt++;
    
    switch (FrameStat)
    {
    case BREAK:
        u8NextBusLvl = 0;
        if (u8TickCnt >= u8BreakLen)
        {
            u8TickCnt = 0;
            FrameStat = DELIMITER;
            u8NextBusLvl = 1;
        }
        break;
        
    case DELIMITER:
        if (u8TickCnt >= u8DelimLen)
        {
            u8TickCnt = 0;
            FrameStat = SYNC;
            u8Byte = 0xAA;
        }
        break;
        
    case SYNC:
        blByteSend = true;
        if (u8TickCnt >= 10)
        {
            u8TickCnt = 0;
            FrameStat = ID;
            u8Byte = u8FrameID;
        }
        break;
        
    case ID:
        blByteSend = true;
        if (u8TickCnt >= 10)
        {
            u8TickCnt = 0;
            FrameStat = DATA;
            u8ByteOnLin = 0;
            if (Direction == M2S)
            {
                u8Byte = u8FrameData[u8ByteOnLin];
            }
            else
            {
                blByteSend = false;
            }
        }
        break;
        
    case DATA:
        if (Direction == M2S)
        {
            blByteSend = true;
        }
        else
        {
            blByteSend = false;
        }
        
        if (u8TickCnt >= 10)
        {
            if (Direction == S2M)
            {
                u8FrameData[u8ByteOnLin] = u8Byte;
            }

            u8ByteOnLin++;
            u8TickCnt = 0;
            
            if (u8ByteOnLin >= u8FrameLen)
            {
                /* Sending/Receiving is ended */
                FrameStat = READY;
                blByteSend = false;
                u8NextBusLvl = 1;
            }
            else if (Direction == M2S)
            {
                u8Byte = u8FrameData[u8ByteOnLin];
            }
        }
        break;
        
    case READY:
    default:
        u8NextBusLvl = 1;
        MyTicker.detach();
        FrameStat  = READY;
        DriverStat = IDLE;
        break;
    }
    
    if (blByteSend == true)
    {
        switch (u8TickCnt)
        {
        case 0:
            /* Start Bit */
            u8NextBusLvl = 0;
            break;
        case 9:
            /* Stop Bit */
            u8NextBusLvl = 1;
            break;
        default:
            u8NextBusLvl = u8Byte & 0x1;
            u8Byte >>= 1;
            break;
        }
    }
}

/* EOF */