comm_lin.c

PIC Kit serial source code.

//==================================================================== 
//--- COPYRIGHT
//==================================================================== 
// Copyright 2007 Microchip Technology Inc.
// 
// Microchip Technology Inc. ("Microchip") licenses this software to
// you solely for use with Microchip products. The software is owned
// by Microchip and is protected under applicable copyright laws. All
// rights reserved.
// 
// SOFTWARE IS PROVIDED IN AN "AS IS." MICROCHIP EXPRESSLY DISCLAIMS ANY
// WARRANTY OF ANY KIND, WHETHER EXPRESS OR IMPLIED, INCLUDING BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
// PARTICULAR PURPOSE, OR NON-INFRINGEMENT. IN NO EVENT SHALL MICROCHIP
// BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT OR CONSEQUENTIAL
// DAMAGES, LOST PROFITS OR LOST DATA, HARM TO YOUR EQUIPMENT, COST OF
// PROCUREMENT OF SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES, ANY CLAIMS
// BY THIRD PARTIES (INCLUDING BUT NOT LIMITED TO ANY DEFENSE THEREOF),
// ANY CLAIMS FOR INDEMNITY OR CONTRIBUTION, OR OTHER SIMILAR COSTS.
// 
//==================================================================== 
//--- TITLE
//==================================================================== 
//    Filename:            comm_lin.c
//    Microcontroller:     PIC18F2550
//    Compiled using:      C18 V3.00
//
//    Author:              Mark Enochson
//    Company:             Microchip Technology Inc.
//
//==================================================================== 
//--- DESCRIPTION
//==================================================================== 
//
//==================================================================== 
//--- HISTORY
//==================================================================== 
//
//    0001 - 03-01-07 - ME
//    -- initial release
//
//    0002 - 03-01-08 - ME
//    -- overhauled module
//    -- changed to interrupt-driven TX
//    -- modified rx_isr
//    -- autobaud detect causes interrupt
//       (previously stayed in ISR, can now with simultaneous
//       MASTER and SLAVE)
//    -- created/defined variable using shared RAM
//    -- eliminated byte of bit flags ... moved to shared RAM
//    -- added SLAVE capability
//    -- set TXEN in INIT function, logic toggles TXIE as necessary
//
//
//    0003 - 04-28-08 - ME
//    -- added definition of bit flag in slave profile:
//       COMM_LIN_SP_IDDEF_ENHANCED_CS_FLAG to indicate a selection
//       of checksum 'type' for applicable node register/identifier
//    -- modified checksum calculation to use 
//       COMM_LIN_SP_IDDEF_ENHANCED_CS_FLAG in the slave profile 
//       to select checksum 'type' - was selected by control block
//
//    0004 - 05-12-08 - ME
//    -- modified rx_isr to avoid posting a SYNC byte event (only data)
//       this allows the DLL/GUI to run more efficiently/quickly
//
//==================================================================== 

//==========================================================
//--- INCLUDES
//==========================================================
#include "project.h"
#include "comm_gen.h"
#include "cbuf.h"
#include "timer0.h"
#include "timer3.h"
#include "comm_lin.h"

//==========================================================
//--- DEFINITIONS / DECLARATIONS
//==========================================================
// (none)

#ifdef   __DEBUG
//#define  __DEBUG_LIN
#endif

#ifdef __DEBUG_LIN
//#define  __DEBUG_LIN_SLAVE_ENABLE
//#define  __DEBUG_LIN_AUX1
//#define  __DEBUG_LIN_AUX2
#endif

//==========================================================
//==========================================================
#ifdef __DEBUG_LIN
//==========================================================
//--- comm_lin_test()
//==========================================================
void comm_lin_test(void)
{
   TD_BYTE i, j, PARITY;
   
   Nop();
   
   cbuf3_init();
   cbuf3_put(0x92);
   cbuf3_put(0x10);
   cbuf3_put(0x11);
   cbuf3_put(0x22);
//   cbuf3_put(0xA9);
   cbuf3_put(0x93);
   cbuf3_put(0x24);
   cbuf3_put(0x12);
   cbuf3_put(0x34);
   cbuf3_put(0x56);
   cbuf3_put(0x81);
   cbuf3_put(0x38);
   cbuf3_put(0x12);
   cbuf3_put(0x00);
   
   COMM_LIN_1_FLAGS = 0;
   comm_flags1_B._b = 0;
   
   comm_state = 0x86;
   cbuf1_put(0x19);
   cbuf1_put(0x02);
   cbuf1_put(0x17);
   cbuf1_put(0x18);

   while(1)
   {
      Nop();
      comm_lin_svc();
   }
      
   return;
   
}
#endif
//==========================================================
//==========================================================


//==========================================================
//--- comm_lin_init()
//==========================================================
//    initialize per CONTROL_BLOCK
//==========================================================
TD_BYTE comm_lin_init(void)
{
   comm_lin_reset();          // idles/disables all hardware used by this module
   comm_lin_config();         // configures hardware
   comm_lin_clear();          // clears dynamic variables/hardware

   cbuf3_init();
   cbuf3_data[1] = 0;         // set slave profile to NULL
   
#ifdef __DEBUG_LIN_AUX1
   LIN_AUX1_PORT = 0;
   LIN_AUX1_TRIS = 0;
#endif

#ifdef __DEBUG_LIN_AUX2
   LIN_AUX2_PORT = 0;
   LIN_AUX2_TRIS = 0;
#endif
   
   return(0);
}

//==========================================================
//--- comm_lin_reset()
//==========================================================
//    RETURN ALL HARDWARE TO RESET/BENIGN STATE
//==========================================================
void comm_lin_reset(void)
{
   //--- DISABLE INTERRUPTS
   PIE1bits.RCIE = 0;
   PIE1bits.TXIE = 0;

   //--- CLEAR H/W REGISTERS
   TXSTA = 0;
   RCSTA = 0;
   BAUDCON = 0;

   //--- SET I/O DIRECTION
   LIN_TX_TRIS = 1;
   LIN_RX_TRIS = 1;
   LIN_CS_TRIS = 1;
   LIN_AFAULT_TRIS = 1;
}

//==========================================================
//--- comm_lin_config()
//==========================================================
//    one-time configuration
//==========================================================
void comm_lin_config(void)
{
   //--- I/O
   LIN_TX_TRIS = 0;
   LIN_RX_TRIS = 1;
   LIN_CS_TRIS = 0;
   LIN_AFAULT_TRIS = 1;

   //--- USART
   BAUDCONbits.BRG16 = 1;
   TXSTAbits.BRGH = 1;
   RCSTAbits.SPEN = 1;

   //--- INTERRUPTS
   IPR1bits.RCIP = 0;
   IPR1bits.TXIP = 0;
   TXSTAbits.TXEN = 1;
}

//==========================================================
//--- comm_lin_clear()
//==========================================================
//    assumes mode/hardware has been properly initialized
//    clears any status/errors without a cold re-init
//
//    anything that could have been changed during operation
//       is returned to default
//    anything that is initialized that never changed 
//       is left alone/unaltered
//    call post processor to set status block
//==========================================================
void comm_lin_clear(void)
{
   TD_BYTE i;
   
   //-----------------------------------
   //--- DISABLE INTERRUPT(S)
   //-----------------------------------
   PIE1bits.RCIE = 0;
   PIE1bits.TXIE = 0;

   //-----------------------------------
   //--- BAUD RATE
   //-----------------------------------
   SPBRG = COMM_CB_LIN_BRG_LO_REG;
   SPBRGH = COMM_CB_LIN_BRG_HI_REG;

   //-----------------------------------
   //--- AUTOBAUD
   //-----------------------------------
   if(BAUDCONbits.ABDEN)
      BAUDCONbits.ABDEN = 0;
   BAUDCONbits.ABDOVF = 0;
   
   //-----------------------------------
   //--- INTERRUPT ENABLE(S)
   //-----------------------------------
   if(PIR1bits.RCIF)
      i = RCREG;
   PIE1bits.RCIE = 1;

   //-----------------------------------
   //--- RX ENABLE
   //-----------------------------------
   if(RCSTAbits.OERR)
      RCSTAbits.CREN = 0;
      
   if(COMM_CB_LIN_RCV_ENABLE_FLAG)
      RCSTAbits.CREN = 1;
   else
      RCSTAbits.CREN = 0;

   //-----------------------------------
   //--- LIN CHIP SELECT
   //-----------------------------------
#ifndef __DEBUG_LIN_AUX1
   if(COMM_CB_LIN_CS_FLAG)
      LIN_CS_PORT = 1;
   else
      LIN_CS_PORT = 0;
#endif

   //-----------------------------------
   //--- OPERATIONAL FLAGS
   //-----------------------------------
   COMM_LIN_0_FLAGS = 0;
   COMM_LIN_1_FLAGS = 0;
      
   //-----------------------------------
   //--- STATUS BLOCK
   //-----------------------------------
   COMM_SB_LIN_REG12 = 0;
   COMM_SB_LIN_REG13 = 0;
   COMM_SB_LIN_REG14 = 0;
   COMM_SB_LIN_REG15 = 0;
   COMM_SB_LIN_REG16 = 0;
   COMM_SB_LIN_REG17 = 0;
   COMM_SB_LIN_REG18 = 0;
   COMM_SB_LIN_REG19 = 0;
   //--- EXECUTE POST PROCESSOR (SETS STATUS)
   comm_lin_postproc();


#ifdef   __DEBUG_LIN_SLAVE_ENABLE
//      COMM_CB_LIN_SLAVE_FLAG = 0;
      COMM_CB_LIN_SLAVE_FLAG = 1;
#endif

}


//==========================================================
//==========================================================
//--- comm_lin_svc()
//==========================================================
//==========================================================
void comm_lin_svc(void)
{

   //---------------------------------------------
   //--- DISABLE INTERRUPTS
   //--- FLAG SET TO REPRESENT EXISTING STATE
   //---------------------------------------------
   COMM_LIN_GIEL1_FLAG = 0;
   if(INTCONbits.GIEL)
   {
      while(INTCONbits.GIEL)
      {
         INTCONbits.GIEL = 0;
      }
      COMM_LIN_GIEL1_FLAG = 1;
   }

   //---------------------------------------------


   //---
#ifndef __DEBUG_LIN_AUX1
   if(COMM_CB_LIN_CS_FLAG)
      LIN_CS_PORT = 1;
   else
      LIN_CS_PORT = 0;
#endif

   //---------------------------------------------
   //--- SWITCH CONTROLLER STATE
   //---------------------------------------------
   switch(comm_state)
   {
      Nop();
      
      //====================================================
      case COMM_TAG_LIN_INIT:
            comm_lin_init();
            break;

      //====================================================
      case COMM_TAG_LIN_XMT_BRK:
      case COMM_TAG_LIN_XMT_BRK_DATA:
      case COMM_TAG_LIN_XMT_FRAME:

         //---------------------------------------
         //--- XMIT BREAK (ALL CMNDS REQUIRE IT)
         //---------------------------------------
         if(not COMM_0_FLAG)
         {

#ifdef __DEBUG_LIN_AUX2
            Nop();
            LIN_AUX2_PORT = 1;
#endif

            if(TXSTAbits.TRMT == 0)
               break;
               
            COMM_LIN_ABAUD_DISABLE_FLAG = 1;          // DISABLE AUTOBAUD
            COMM_0_FLAG = 1;                          // SET OP FLAG
            TXSTAbits.SENDB = 1;                      // SET 'BREAK' CONTROL
            PIE1bits.TXIE = 1;                        // ENABLE INT(S)
            TXREG = 0;                                // LOAD TXREG WITH DUMMY ZERO
            COMM_LIN_TX_SVC_FLAG = 1;                 // ISR FLAG TO CALL SERVICE
            comm_led_busy_data();                     // SET LED BUSY
            if(COMM_CB_LIN_EVENT_EN_BREAK_TX_FLAG)
               comm_post_event(COMM_TAG_LIN_EVENT_BREAK_TX);

#ifdef __DEBUG_LIN_AUX2
            LIN_AUX2_PORT = 0;
#endif
            break;
         }

         //---------------------------------------
         //--- IF BREAK ONLY, WAIT UNTIL DONE ...
         //---------------------------------------
         if(comm_state == COMM_TAG_LIN_XMT_BRK) 
         {
            if(PIR1bits.TXIF)
            {
               PIE1bits.TXIE = 0;                  // DISABLE INT(S) - DONE!
               COMM_LIN_TX_SVC_FLAG = 0;           // RST FLAG: TX SERVICE