File content as of revision 7:199f109eb0c6:

/** PCA9629 library
 *
 *  @author  Akifumi (Tedd) OKANO, NXP Semiconductors
 *  @version 1.1
 *  @date    23-Jul-2012
 *
 *  revision history
 *      version 1.0 (24-Apr-2011) : Initial version
 *      version 1.1 (23-Jul-2012) : API modification
 *                                  Correction for comments
 *
 *  Released under the MIT License: http://mbed.org/license/mit
 *
 *  An operation sample of PCU9629 stepper motor controller.
 *  The mbed accesses the PCU9629 registers through I2C.
 *
 *  About PCA9629:
 *    http://www.nxp.com/products/interface_and_connectivity/i2c/i2c_bus_controller_and_bridge_ics/PCA9629PW.html
 */

#include    "mbed.h"
#include    "PCA9629.h"

#define     STEP_RESOLUTION     333333      //  1/(3e-6) = 333333

char *reg_name[] = {
    "MODE", "SUBADR1", "SUBADR2", "SUBADR3", "ALLCALLADR", "WDTC", "WDMOD", "IP",
    "INTSTAT", "OP", "IOC", "MSK", "CLRINT", "INTMODE1", "INTMODE2", "INT_ACT_SETUP",
    "INT_MRT_SETUP", "INT_ES_SETUP", "SETMODE", "PHCNTL", "SROTNL", "SROTNH",
    "CWPWL", "CWPWH", "CCWPWL", "CCWPWH",
    "CWSCOUNTL", "CWSCOUNTH", "CCWSCOUNTL", "CCWSCOUNTH",
    "CWRCOUNTL", "CWRCOUNTH", "CCWRCOUNTL", "CCWRCOUNTH",
    "EXTRASTEPS0", "EXTRASTEPS1", "RAMPX", "LOOPDLY", "MCNTL"
};

PCA9629::PCA9629(
    PinName I2C_sda,
    PinName I2C_scl,
    short   steps_per_rotation,
    char    I2C_address
) : i2c( I2C_sda, I2C_scl ), i2c_addr( I2C_address ) {

    i2c.frequency( 400 * 1000 );
    software_reset();
    init_registers();
}

void PCA9629::software_reset( void ) {
    char    v   = 0x06;
    
    i2c.write( 0x00, &v, 1 );
    wait_ms( 1 );
}

void PCA9629::init_registers( void ) {
    char    init_array[] = { 0x80,                                                //  register access start address (0x00) with incremental access flag (MSB)
                             0x30, 0xE2, 0xE4, 0xE6, 0xE0, 0x02, 0x10,             //  for registers MODE - WDCNTL (0x00 - 0x06
                             0x00, 0x00,                                           //  for registers IP and INTSTAT (0x07, 0x08)
                             0x07, 0x0F, 0x00, 0x0F, 0x0F, 0x00, 0x03, 0x02, 0x01, //  for registers OP - INT_AUTO_CLR (0x09 - 0x11)
                             0x00, 0x00, 0x30, 0x00, 0x82, 0x66, 0x82, 0x06,       //  for registers SETMODE - CCWPWH (0x12 - 0x19)
                             0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF,       //  for registers CWSCOUNTL - CCWRCOUNTH (0x1A - 0x21)
                             0x00, 0x00,                                           //  for registers EXTRASTEPS0 and EXTRASTEPS1 (0x22, 0x23)
                             0x00, 0x00, 0x00                                      //  for registers RMPCNTL - MCNTL (0x24 - 0x26)
                           };

    set_all_registers( init_array, sizeof( init_array ) );
}

void PCA9629::set_all_registers( char *a, char size ) {
    int     error_code;

    error_code  = i2c.write( i2c_addr, a, size );

    if ( error_code )
        error( "error @ initializing PCA9629" );
}

void PCA9629::write( RegisterName register_name, char value ) {
    int     error_code;
    char    cmd[ 2 ];

    cmd[ 0 ]    = register_name;
    cmd[ 1 ]    = value;

    error_code  = i2c.write( i2c_addr, cmd, 2 );

    if ( error_code )
        error( "PCA9629 writing failed\r\n" );
}

void PCA9629::write( RegisterNameFor16bitAccess register_name, short value ) {
    int     error_code;
    char    cmd[ 3 ];

    cmd[ 0 ]    = register_name;
    cmd[ 1 ]    = value & 0xFF;
    cmd[ 2 ]    = value >> 8;

    error_code  = i2c.write( i2c_addr, cmd, 3 );

    if ( error_code )
        error( "PCA9629 writing failed\r\n" );
}

char PCA9629::read( RegisterName register_name ) {
    int     error_code;
    char    cmd;
    char    data;

    cmd = register_name;

    error_code  = i2c.write( i2c_addr, &cmd, 1, false );

    if ( error_code )
        error( "PCA9629 reading (command phase) failed\r\n" );

    error_code  = i2c.read( i2c_addr, &data, 1 );

    if ( error_code )
        error( "PCA9629 reading (data phase) failed\r\n" );

    return ( data );
}

short PCA9629::read( RegisterNameFor16bitAccess register_name ) {
    int     error_code;
    char    cmd;
    char    data[ 2 ];

    cmd = register_name;

    error_code  = i2c.write( i2c_addr, &cmd, 1, false );

    if ( error_code )
        error( "PCA9629 reading (command phase) failed\r\n" );

    error_code  = i2c.read( i2c_addr, data, 2 );

    if ( error_code )
        error( "PCA9629 reading (data phase) failed\r\n" );

    return ( data[ 1 ] << 8 | data[ 0 ] );
}

void PCA9629::start( Direction dir ) {
    write( MCNTL, 0xA8 | dir );
}

void PCA9629::stop( void ) {
    write( MCNTL, 0x00 );
}


short PCA9629::pps( Direction dir, PrescalerRange prescaler, int pps ) {
    int     step_pulse_width;

    step_pulse_width    = STEP_RESOLUTION / ((1 << prescaler) * pps);

    if ( step_pulse_width & 0xE000 ) {  //error( "pps setting: out of range" );
        step_pulse_width    = 0x1FFF;
        printf( "the pps forced in to the range that user specified.. %fpps\r\n", (float)STEP_RESOLUTION / ((float)0x1FFF * (float)(1 << prescaler)) );
    }
    if ( !step_pulse_width ) {  //error( "pps setting: out of range" );
        step_pulse_width    = 0x1;
        printf( "the pps forced in to the range that user specified.. %fpps\r\n", (float)STEP_RESOLUTION / (float)(1 << prescaler) );
    }

    step_pulse_width    |= (prescaler << 13);

    write( (dir == CW) ? CW__STEP_WIDTH : CCW_STEP_WIDTH, step_pulse_width );

    return ( step_pulse_width );
}

short PCA9629::pps( Direction dir, float pulse_per_second ) {
    char    p       = 0;
    char    ratio;

    ratio   = (char)(40.6901 / pulse_per_second);

    p   = (ratio & 0x01) ? 1 : p;
    p   = (ratio & 0x02) ? 2 : p;
    p   = (ratio & 0x04) ? 3 : p;
    p   = (ratio & 0x08) ? 4 : p;
    p   = (ratio & 0x10) ? 5 : p;
    p   = (ratio & 0x20) ? 6 : p;
    p   = (ratio & 0x40) ? 7 : p;

    return ( pps( dir, (PrescalerRange)p, (int)pulse_per_second ) );
}

void PCA9629::rotations( Direction dir, int rotation_count ) {
    write( (dir == CW) ? CW__ROTATION_COUNT : CCW_ROTATION_COUNT, rotation_count );
}

void PCA9629::steps( Direction dir, int step_count ) {
    write( (dir == CW) ? CW__STEP_COUNT : CCW_STEP_COUNT, step_count );
}

void PCA9629::rotations_and_steps( Direction dir, int rotation_count, int step_count ) {
    rotations( dir, rotation_count );
    steps( dir, step_count );
}

void PCA9629::register_dump( void ) {
    char    data[ 0x27 ];
    char    cmd = 0x80;
    int     i;
    int     j;

    i2c.write( i2c_addr, &cmd, 1 );
    i2c.read( i2c_addr, data, sizeof( data ) );

    printf( "PCA9629 register dump\r\n" );

    for ( i = 0, j = 0x14; i <= 0x12; i++, j++ )
        printf( "  %-13s (0x%02X): 0x%02X    %-13s (0x%02X): 0x%02X\r\n", reg_name[ i ], i, data[ i ], reg_name[ j ], j, data[ j ] );

    printf( "  %-13s (0x%02X): 0x%02X\r\n", reg_name[ 0x13 ], 0x13, data[ 0x13 ] );
}


void PCA9629::speed_change( unsigned short pw ) {
    char    cmd0[]   = { PCA9629::MCNTL, 0x00};                         //  data for stop the motor
    char    cmd1[]   = { PCA9629::CW__STEP_WIDTH, pw & 0xFF, pw >> 8 }; //  data for rewrite pulse width
    char    cmd2[]   = { PCA9629::MCNTL, 0xB4};   //  start             //  data for start again
    wait_us(10);

    i2c.write( i2c_addr, cmd0, sizeof( cmd0 ), true );  //  stop the motor
    wait_us(50);
    i2c.write( i2c_addr, cmd1, sizeof( cmd1 ), true );  //  rewrite pulse width
    i2c.write( i2c_addr, cmd2, sizeof( cmd2 ), false ); //  start again
}