File content as of revision 11:61a025e8ab68:

#include    "mbed.h"
#include    "MARY_CAMERA.h"

#define PARAM_NUM       99
#define CAM_I2C_ADDR    0x42

#define     RESET_PULSE_WIDTH   100     //  mili-seconds
#define     RESET_RECOVERY_TIME 100     //  mili-seconds

#define     COMMAND_WRITE                   0x00
#define     COMMAND_READ                    0x80
#define     COMMAND_ADDR_INCREMENT          0x20

#define     MEMORY_ADDR_LOW__REGISTER       0x0
#define     MEMORY_ADDR_MID__REGISTER       0x1
#define     MEMORY_ADDR_HIGH_REGISTER       0x2
#define     CAMERA_DATA_REGISTER            0x8
#define     CONTROL_DATA_REGISTER           0x3
#define     STATUS_REGISTER                 0x4

#define     CONTROL__PAUSE_BUFFER_UPDATE    0x01
#define     CONTROL__RESUME_BUFFER_UPDATE   0x00


MARY_CAMERA::MARY_CAMERA(
    PinName SPI_mosi,
    PinName SPI_miso,
    PinName SPI_sck,
    PinName SPI_cs,
    PinName cam_reset,
    PinName I2C_sda,
    PinName I2C_scl
) :
    _spi( SPI_mosi, SPI_miso, SPI_sck ),
    _cs( SPI_cs ),
    _reset( cam_reset ),
    _i2c( I2C_sda, I2C_scl )
{
#ifdef IGNORE_INITIALIZATION_ERROR
    init();
#else
    if ( 0 != init() )
        error( "camera initialization failed." );
#endif
}

int MARY_CAMERA::init( void )
{
    const char camera_register_setting[2][PARAM_NUM] = {
        {
            0x01,0x02,0x03,0x0c,0x0e,0x0f,0x11,0x12,0x15,0x16,0x17,0x18,0x19,0x1a,0x1e,0x21,0x22,
            0x29,0x32,0x33,0x34,0x35,0x37,0x38,0x39,0x3b,0x3c,0x3d,0x3e,0x3f,0x40,0x41,0x41,
            0x43,0x44,0x45,0x46,0x47,0x48,0x4b,0x4c,0x4d,0x4e,0x4f,0x50,0x51,0x52,0x53,
            0x54,0x56,0x58,0x59,0x5a,0x5b,0x5c,0x5d,0x5e,0x69,0x6a,0x6b,0x6c,0x6d,0x6e,
            0x6f,0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x8d,0x8e,0x8f,0x90,
            0x91,0x96,0x96,0x97,0x98,0x99,0x9a,0x9a,0x9b,0x9c,0x9d,0x9e,0xa2,0xa4,0xb0,
            0xb1,0xb2,0xb3,0xb8,0xc8,0xc9
        },
        {
            0x40,0x60,0x02,0x0c,0x61,0x4b,0x81,0x04,0x00,0x02,0x39,0x03,0x03,0x7b,0x37,0x02,0x91,
            0x07,0x80,0x0b,0x11,0x0b,0x1d,0x71,0x2a,0x12,0x78,0xc3,0x11,0x00,0xd0,0x08,0x38,
            0x0a,0xf0,0x34,0x58,0x28,0x3a,0x09,0x00,0x40,0x20,0x80,0x80,0x00,0x22,0x5e,
            0x80,0x40,0x9e,0x88,0x88,0x44,0x67,0x49,0x0e,0x00,0x40,0x0a,0x0a,0x55,0x11,
            0x9f,0x3a,0x35,0x11,0xf1,0x10,0x05,0xe1,0x01,0x04,0x01,0x4f,0x00,0x00,0x00,
            0x00,0x00,0x00,0x30,0x20,0x30,0x00,0x84,0x29,0x03,0x4c,0x3f,0x52,0x88,0x84,
            0x0c,0x0e,0x82,0x0a,0xf0,0x60
        }
    };
    char    s[ 2 ];

    //  SPI settings

    _cs     = 1;                        //  set ChipSelect signal HIGH
    _spi.format( 8 );                   //  camera SPI : 8bits/transfer
    _spi.frequency( SPI_FREQUENCY );    //  SPI frequency setting

    //  reset

    _reset = 0;
    wait_ms( RESET_PULSE_WIDTH );   //  assert RESET signal
    _reset = 1;
    wait_ms( RESET_RECOVERY_TIME ); //  deassert RESET signal

    //  set camera registers

    for ( int i = 0; i < PARAM_NUM; i++ ) {
        s[ 0 ]  = camera_register_setting[ 0 ][ i ];    //  register sddress
        s[ 1 ]  = camera_register_setting[ 1 ][ i ];    //  register value

        //  camera register setting through I2C
        //  abort initialization if the I2C has problem
        
        if ( 0 != (_error_state = _i2c.write( CAM_I2C_ADDR, s, 2 )) )
            break;  

        wait_ms( 20 );  //  camera register writing requires this interval
    }

    return _error_state;    //  return non-zero if I2C access failed
}

int MARY_CAMERA::ready( void )
{
    return _error_state;    //  return last state of I2C access
}

void MARY_CAMERA::transfer_a_line( short *p, int line_number, int x_offset, int n_of_pixels )
{
    char    tmp;

    //  set camera module's buffer address
    set_address( line_number * BYTE_PER_LINE + x_offset * BYTE_PER_PIXEL );

    //  put a read command, first return byte should be ignored
    read_register( CAMERA_DATA_REGISTER );

    for( int x = 0; x < n_of_pixels; x++ ) {
        //  perform 2 bytes read. a pixel data is in RGB565 format (16bits)
        tmp     = read_register( CAMERA_DATA_REGISTER );                //  read lower byte
        *p++    = (read_register( CAMERA_DATA_REGISTER ) << 8) | tmp;   //  read upper byte
    }
}

void MARY_CAMERA::open_transfer( void )
{
    //  send command to pause the camera buffer update
    write_register( CONTROL_DATA_REGISTER, CONTROL__PAUSE_BUFFER_UPDATE );

    //  read status register (first return byte should be ignored)
    read_register( STATUS_REGISTER );

    //  wait until the status register become 0x51(ready to transfer data)
    while ( 0x51 != read_register( STATUS_REGISTER ) )
        ;
}

void MARY_CAMERA::close_transfer( void )
{
    //  send command to resume the camera buffer update
    write_register( CONTROL_DATA_REGISTER, CONTROL__RESUME_BUFFER_UPDATE );

    //  read status register (first return byte should be ignored)
    read_register( STATUS_REGISTER );

    //  wait until the status register become 0x50(camera updating the buffer)
    while ( 0x50 != read_register( STATUS_REGISTER ) )
        ;
}

void MARY_CAMERA::set_address( int address )
{
    //  set memory address (3 bytes)
    
    write_register( MEMORY_ADDR_LOW__REGISTER, (address >>  0) & 0xFF );
    write_register( MEMORY_ADDR_MID__REGISTER, (address >>  8) & 0xFF );
    write_register( MEMORY_ADDR_HIGH_REGISTER, (address >> 16) & 0xFF );
}

void MARY_CAMERA::write_register( char reg, char value )
{
    //  camera register write
    
    send_spi( COMMAND_WRITE | reg );    //  send command and register number
    send_spi( value );                  //  send register value
}

int MARY_CAMERA::read_register( char reg )
{
    //  camera register read
    //  returning current data in SPI buffer (data returned by previous command)

    return ( send_spi( COMMAND_READ | reg | ((reg == CAMERA_DATA_REGISTER) ? COMMAND_ADDR_INCREMENT : 0x00) ) );
}

int MARY_CAMERA::send_spi( char data )
{
    int     tmp;
    
    //  SPI access

    _cs     = 0;
    tmp     = _spi.write( data );
    _cs     = 1;
    
    return ( tmp );
}