i2c.c

基于瑞萨 M16C 的最新版本 IIC 通信

// ---------------------------------------------------------------------------
//  DISCLAIMER:                                                       		
//  We (RENESAS TECHNOLOGY EUROPE) do not warrant that the Software is
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//  Under no circumstances are we liable for any of the following:
//
//  1. third-party claims against you for losses or damages;
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//  3. economic consequential damages (including lost profits or
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//  We do not warrant uninterrupted or error free operation of the
//  Software. We have no obligation to provide service, defect
//  correction, or any maintenance for the Software. We have no
//  obligation to supply any Software updates or enhancements to you
//  even if such are or later become available.
//
//  IF YOU DOWNLOAD OR USE THIS SOFTWARE YOU AGREE TO THESE TERMS.
//
//  THERE ARE NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING THE
//  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
//  PARTICULAR PURPOSE.
// ---------------------------------------------------------------------------
//  Copyright (c) 2005 RENESAS TECHNOLOGY EUROPE   All rights reserved.
// ---------------------------------------------------------------------------
//              S O U R C E   F O R M A T
// ---------------------------------------------------------------------------
// tab width 4 (tab at 4 8 12 ...) 				
// ---------------------------------------------------------------------------
//  Project Name: I2C			
//  File        : i2c.c	
//  Description : access i2c external device 		 	
// ---------------------------------------------------------------------------
//  Supported   : IAR M16C C/EC++ Compiler V2.12A/W32
//  Compiler      							
// ---------------------------------------------------------------------------
//              R E V I S I O N
// ---------------------------------------------------------------------------
//  Supported Compiler : IAR
// ---------------------------------------------------------------------------
//	              R E V I S I O N   H I S T O R Y			
// ---------------------------------------------------------------------------
//  Date         	Ver  Author  Description			
// ---------------------------------------------------------------------------
//  25/01/2005   	1.0  INFORT/TMA    Creation				
// ---------------------------------------------------------------------------
//              R E M A R K S
// Tested on device : M16C26 & M16C62P on UART2
// Used Peripherals : UARTi
// Used Interrupts : UARTiRX / UARTiTX / BUS_COLLISION_UARTi
// ---------------------------------------------------------------------------

// ---------------------------------------------------------------------------
// Include declaration
// ---------------------------------------------------------------------------
#include "i2c.h"
#include "uart.h"
// ---------------------------------------------------------------------------
// Global variables declaration
// ---------------------------------------------------------------------------
struct stI2CAddress
{
  unsigned char rw:1;
  unsigned char address:7;
};

typedef union
{
  unsigned char byte;
  struct stI2CAddress bit;
}tI2CAddress;



static tI2CAddress slaveAddress;
static unsigned short readIndex;
static unsigned short totalReadLength;
static unsigned char *ptrReadData;
static unsigned short writeIndex;
static unsigned short writeLength;
static unsigned char *ptrWriteData;
static I2CStatus currentStatus;


// ---------------------------------------------------------------------------
// Initialise I睠 line
// Data is sent by DMA1 triggered by ACK reception
// ---------------------------------------------------------------------------
// Input Parameters :     None
// ---------------------------------------------------------------------------
// Returned Parameters :  None
// ---------------------------------------------------------------------------
// Modified globales:     None
// ---------------------------------------------------------------------------
void I2C_init()
{

  UiMR    = 0x0A;   // I睠 mode mode ext. clock (slave mode)
  UiBRG   = I2C_100_KB_SPEED; // 100KBPS (this depends on used Xin/CPU clock)
  UiC0    = 0xB0;   // MSB first,Tx at raising edge of CK, f1,Nch,CTS disable
  UiSMR   = 0x01;   // I睠bus mode,Arbitration lost flag Update per bit
                    // Bus collision detect at raising edge of CK
  UiSMR2  = 0x11;   // ACK/NACK interrupt,disable SDA/SCL,UART init
  UiSMR3  = 0x62;   // SDA delay = 3 to 4-cycle of BRG count source
  UiSMR4  = 0x30;   // NACK data output(SDA=SCL="H")
  UiC1    = 0x15;   // Transfer/Receive enable
#ifdef  DMA1_USED
  DM1IC.BYTE   = INT_DISABLE;  // Disable DMA1 Interrupt
  DM1SL.BYTE   = DMA1_ACK_TRIG_SOURCE;
#endif
  STA_STP_IC  = STA_STP_IPL;  // Start condition interrupt enable
  ACK_IC      = INT_DISABLE;  // ACK int. disable
  NACK_IC     = INT_DISABLE;  // NACK int. enable
  currentStatus.byte = I2C_FREE_NO_ERROR;

}

// ---------------------------------------------------------------------------
// Send Data on I睠 line
// Data is sent by DMA1 triggered by ACK reception
// ---------------------------------------------------------------------------
// Input Parameters :
// 1- Slave address
// 2- Pointer to transmit buffer
// 3- Number of data to transmit
// ---------------------------------------------------------------------------
// Returned Parameters :
// TRUE or FALSE if data can be transmited
// ---------------------------------------------------------------------------
// Modified globales:   None
// ---------------------------------------------------------------------------
tBoolean I2C_MasterWrite(unsigned char address, unsigned char * ptrData, unsigned short length)
{
  if(currentStatus.bit.busy==TRUE)
    return FALSE;
  currentStatus.byte =I2C_BUSY_NO_ERROR;
#ifdef  DMA1_USED
  // DMA Configuration
  DAR1.DWORD    = (int)&UiTB;    	// Destination
  TCR1.WORD    	= length-1;       	// Size (minus one due to DMA specification)
  SAR1.DWORD    = (int)ptrData;  	// Source
  DM1CON.BYTE  	= 0x19;           	// Memory to fixed destination single transfert
  DM1IC.BYTE  	= DMA1_IPL;       	// Enable DMA1 Interrupt
#else
  writeLength     = length;    	 // Size (minus one due to DMA specification)
  ptrWriteData    = ptrData;  		// Source
  writeIndex      = 0;
#endif
  slaveAddress.bit.address = address;
  slaveAddress.bit.rw = 0;     // Write mode
  UiSMR   = 0x01;   // All bit clear without bit0
  UiSMR4  = 0x70;   // SCL output STOP enable (SCLHI=1)
  UiMR    = 0x00;   // Disable UART function
  UiMR    = 0x02;   // Enable IIC mode, internal clock
  UiC1    = 0x10;   // Transmit/Receive disable
  UiSMR2  = 0x02;   // UART init. disable,Clock sync. enable
  UiSMR4  = 0x71;   // Start condition generate (STSPSEL=0/STAREQ=1)
  UiSMR4  = 0x09;   // STSP output enable (STSPSEL=1/STAREQ=1)
  return TRUE;
}
// ---------------------------------------------------------------------------
// Read Data on I睠 line
// Data is received by DMA1 triggered by ACK reception
// ---------------------------------------------------------------------------
// Input Parameters :
// 1- Slave address
// 2- Pointer to receive buffer
// 3- Number of data to receive
// ---------------------------------------------------------------------------
// Returned Parameters :
// TRUE or FALSE if data can be read
// ---------------------------------------------------------------------------
// Modified globales:   None
// ---------------------------------------------------------------------------
tBoolean I2C_MasterRead(unsigned char address, unsigned char *ptrData, unsigned short length)
{
  if(currentStatus.bit.busy==TRUE)
    return FALSE;
  if(length==0)
    return TRUE;
  currentStatus.byte =I2C_BUSY_NO_ERROR;
  ptrReadData = ptrData;
  readIndex = 0;
  totalReadLength = length;
  slaveAddress.bit.address = address;
  slaveAddress.bit.rw=1;//Read mode
  UiSMR   = 0x01;   // All bit clear without bit0
  UiSMR4  = 0x70;   // SCL output STOP enable (SCLHI=1)
  UiMR    = 0x00;   // Disable UART function