camconfig.c

The AVRcam source files were built using the WinAVR distribution (version 3.3.1 of GCC). I haven t

/**********************************************************
    Module Name: CamConfig.c
    Module Date: 04/10/2004
    Module Auth: John Orlando 
    Copyright (c) 2004 John Orlando  All Rights Reserved 

    Description: This module is responsible for the
    high-level configuration activities of the OV6620
    camera module.  This module interfaces with the
    I2CInterface module to perform this configuration.
    ***********************************************************/

/*  Includes */
#include <avr/io.h>
#include "CamConfig.h"
#include "I2CInterface.h"
#include "CommonDefs.h"
#include "Utility.h"

/**********************************************************/
/*  Definitions */
/* The length of an I2C command is made up of a register address
    plus the actual value of the register */
#define SIZE_OF_I2C_CMD 2
#define MAX_NUM_CONFIG_CMDS 8
#define CAM_CONFIG_TX_FIFO_SIZE MAX_NUM_CONFIG_CMDS
#define CAM_CONFIG_TX_FIFO_MASK CAM_CONFIG_TX_FIFO_SIZE-1

/*  Local Variables */

/*  Local Structures and Typedefs */

/*  Local Function Prototypes */
static i2cCmd_t CamConfig_readTxFifo(void);

/*  Extern Variables */
i2cCmd_t 		CamConfig_txFifo[CAM_CONFIG_TX_FIFO_SIZE];
unsigned char CamConfig_txFifoHead=0;
unsigned char CamConfig_txFifoTail=0;

/***********************************************************
    Function Name: CamConfig_init
    Function Description: This function is responsible for
    performing the initial configuration of the camera.
    Inputs:  none
    Outputs: none
    ***********************************************************/
void CamConfig_init(void)
{
    CamConfig_setCamReg(0x14,0x20);  /* reduce frame size */
    CamConfig_setCamReg(0x39,0x40);  /* gate PCLK with HREF */
    CamConfig_setCamReg(0x12,0x28);  /* set RGB mode, with no AWB */
    CamConfig_setCamReg(0x28,0x05);  /* set color sequencer */

    /* send the first four cmds in the I2C fifo */
    CamConfig_sendFifoCmds();

    //CamConfig_setCamReg(0x16,0x09);  /* assert HREF in odd frames only */
    //CamConfig_sendFifoCmds();

}


/***********************************************************
    Function Name: CamConfig_setCamReg
    Function Description: This function is responsible for
    creating an I2C cmd structure and placing it into the
    cmd fifo.
    Inputs:  reg - the register to modify
    val - the new value of the register
    Outputs: none
    ***********************************************************/
void CamConfig_setCamReg(unsigned char reg, unsigned char val)
{
    i2cCmd_t cmd;

    cmd.configReg = reg;
    cmd.data = val;
#ifndef SIMULATION
    CamConfig_writeTxFifo(cmd);
#endif
}
/***********************************************************
    Function Name: CamConfig_sendFifoCmds
    Function Description: This function is responsible for
    sending the entire contents of the config fifo.  This
    function won't return until the configuration process
    is complete (or an error is encountered).
    Inputs:  none
    Outputs: none
    Note: Since this function is written to use the TWI
    interrupt in the I2CInterface module, there will be
    some busy-waiting here...no big deal, since we end up
    having to trash the frame that we are executing this
    slave write in anyway (since we can't meet the strict
    timing requirements and write i2c at the same time).
    ***********************************************************/
void CamConfig_sendFifoCmds(void)
{
    i2cCmd_t cmd;

    while (CamConfig_txFifoHead != CamConfig_txFifoTail)
    {
        cmd = CamConfig_readTxFifo();
        I2CInt_writeData(CAM_ADDRESS,&cmd.configReg,SIZE_OF_I2C_CMD);
        Utility_delay(100);
        /* wait for the I2C transaction to complete */
        while(I2CInt_isI2cBusy() == TRUE);
    }
}

/***********************************************************
    Function Name: CamConfig_writeTxFifo
    Function Description: This function is responsible for
    adding a new command to the tx fifo.  It adjusts all
    needed pointers.
    Inputs:  cmd - the i2cCmd_t to add to the fifo
    Outputs: bool_t - indicating if writing to the fifo
    causes it to wrap
    ***********************************************************/
bool_t CamConfig_writeTxFifo(i2cCmd_t cmd)
{
    unsigned char tmpHead;
    bool_t retVal = TRUE;

    CamConfig_txFifo[CamConfig_txFifoHead] = cmd;

    /* see if we need to wrap */
    tmpHead = (CamConfig_txFifoHead+1) & (CAM_CONFIG_TX_FIFO_MASK);
    CamConfig_txFifoHead = tmpHead;

    /* check to see if we have filled up the queue */
    if (CamConfig_txFifoHead == CamConfig_txFifoTail)
    {
        /* we wrapped the fifo...return false */
        retVal = FALSE;
    }
    return(retVal);
}

/***********************************************************
    Function Name: CamConfig_readTxFifo
    Function Description: This function is responsible for
    reading a cmd out of the tx fifo.
    Inputs:  none
    Outputs: i2cCmd_t - the cmd read from the fifo
    ***********************************************************/
static i2cCmd_t CamConfig_readTxFifo(void)
{
    i2cCmd_t cmd;
    unsigned char tmpTail;

    /* just return the current tail from the rx fifo */
    cmd = CamConfig_txFifo[CamConfig_txFifoTail];
    tmpTail = (CamConfig_txFifoTail+1) & (CAM_CONFIG_TX_FIFO_MASK);
    CamConfig_txFifoTail = tmpTail;

    return(cmd);
}