InetrfaceProducts NXP / PCA9955

PCA9955 16 channel current drive(sink) LED driver class library

Dependents:   PCA9955_Hello

PCA9955.cpp@0:2e6f5ac1b29b, 2012-08-10 (annotated)

Committer:
nxp_ip
Date:
Fri Aug 10 01:39:02 2012 +0000
Revision:
0:2e6f5ac1b29b
PCA9955 sample code

Who changed what in which revision?

UserRevisionLine numberNew contents of line
nxp_ip 0:2e6f5ac1b29b 1 /** PCA9955 constant current LED driver control library
nxp_ip 0:2e6f5ac1b29b 2 *
nxp_ip 0:2e6f5ac1b29b 3 * @class PCA9955
nxp_ip 0:2e6f5ac1b29b 4 * @author NXP Semiconductors Japan
nxp_ip 0:2e6f5ac1b29b 5 * @version 0.5(15-Jun-2011) (publish 10-Aug-2012)
nxp_ip 0:2e6f5ac1b29b 6 *
nxp_ip 0:2e6f5ac1b29b 7 * Copyright: 2011 NXP Semiconductors
nxp_ip 0:2e6f5ac1b29b 8 * Released under the MIT License: http://mbed.org/license/mit
nxp_ip 0:2e6f5ac1b29b 9 * This is a library that controls PCA9955 a constant current LED driver
nxp_ip 0:2e6f5ac1b29b 10 * Example:
nxp_ip 0:2e6f5ac1b29b 11 * @code
nxp_ip 0:2e6f5ac1b29b 12 * #include "mbed.h"
nxp_ip 0:2e6f5ac1b29b 13 * #include "PCA9955.h"
nxp_ip 0:2e6f5ac1b29b 14 *
nxp_ip 0:2e6f5ac1b29b 15 * #define MAX_IREF 0x20
nxp_ip 0:2e6f5ac1b29b 16 *
nxp_ip 0:2e6f5ac1b29b 17 * PCA9955 led_driver( p28, p27, 0xC0 ); // making an instance of PCA9955
nxp_ip 0:2e6f5ac1b29b 18 *
nxp_ip 0:2e6f5ac1b29b 19 * main()
nxp_ip 0:2e6f5ac1b29b 20 * {
nxp_ip 0:2e6f5ac1b29b 21 * char v[ 16 ] = { 0xFF };
nxp_ip 0:2e6f5ac1b29b 22 * int sel;
nxp_ip 0:2e6f5ac1b29b 23 *
nxp_ip 0:2e6f5ac1b29b 24 * srand( 0 );
nxp_ip 0:2e6f5ac1b29b 25 *
nxp_ip 0:2e6f5ac1b29b 26 * led_driver = 0xFFFF;
nxp_ip 0:2e6f5ac1b29b 27 * led_driver.set_all_intensity( v ); // PWM
nxp_ip 0:2e6f5ac1b29b 28 * led_driver.set_all_intensity( MAX_IREF, true ); // IREF
nxp_ip 0:2e6f5ac1b29b 29 *
nxp_ip 0:2e6f5ac1b29b 30 * while ( 1 ) {
nxp_ip 0:2e6f5ac1b29b 31 * for ( sel = 0; sel < 16; sel++ ) {
nxp_ip 0:2e6f5ac1b29b 32 * v[ sel ] = (char)((float)(v[ sel ]) * 0.8);
nxp_ip 0:2e6f5ac1b29b 33 * }
nxp_ip 0:2e6f5ac1b29b 34 *
nxp_ip 0:2e6f5ac1b29b 35 * v[ rand() % 16 ] = 0xFF;
nxp_ip 0:2e6f5ac1b29b 36 *
nxp_ip 0:2e6f5ac1b29b 37 * led_driver.set_all_intensity( v ); // PWM
nxp_ip 0:2e6f5ac1b29b 38 * wait( 0.05 );
nxp_ip 0:2e6f5ac1b29b 39 * }
nxp_ip 0:2e6f5ac1b29b 40 * }
nxp_ip 0:2e6f5ac1b29b 41 * @endcode
nxp_ip 0:2e6f5ac1b29b 42 */
nxp_ip 0:2e6f5ac1b29b 43
nxp_ip 0:2e6f5ac1b29b 44 #include "mbed.h"
nxp_ip 0:2e6f5ac1b29b 45 #include "PCA9955.h"
nxp_ip 0:2e6f5ac1b29b 46
nxp_ip 0:2e6f5ac1b29b 47 PCA9955::PCA9955(
nxp_ip 0:2e6f5ac1b29b 48 PinName I2C_sda,
nxp_ip 0:2e6f5ac1b29b 49 PinName I2C_scl,
nxp_ip 0:2e6f5ac1b29b 50 char I2C_address = PCA9955_ADDR
nxp_ip 0:2e6f5ac1b29b 51 ) : i2c( I2C_sda, I2C_scl ), i2c_addr( I2C_address ) {
nxp_ip 0:2e6f5ac1b29b 52
nxp_ip 0:2e6f5ac1b29b 53 i2c.frequency( 400 * 1000 );
nxp_ip 0:2e6f5ac1b29b 54 write( init_array, sizeof( init_array[42] ) );
nxp_ip 0:2e6f5ac1b29b 55 }
nxp_ip 0:2e6f5ac1b29b 56
nxp_ip 0:2e6f5ac1b29b 57 void PCA9955::set_single_individual_intensity( char port, char val, int iref ) {
nxp_ip 0:2e6f5ac1b29b 58 write( (command_reg)((iref ? IREF_REGISTER_START : PWM_REGISTER_START) + port), val );
nxp_ip 0:2e6f5ac1b29b 59 }
nxp_ip 0:2e6f5ac1b29b 60
nxp_ip 0:2e6f5ac1b29b 61 void PCA9955::set_all_intensity( char *p, int iref ) {
nxp_ip 0:2e6f5ac1b29b 62 char pwm[ PCA9955_N_OF_PORTS + 1 ] = { AUTO_INCREMENT | (iref ? IREF_REGISTER_START : PWM_REGISTER_START) };
nxp_ip 0:2e6f5ac1b29b 63
nxp_ip 0:2e6f5ac1b29b 64 for ( int i = 1; i <= PCA9955_N_OF_PORTS; i++ )
nxp_ip 0:2e6f5ac1b29b 65 pwm[ i ] = *p++;
nxp_ip 0:2e6f5ac1b29b 66
nxp_ip 0:2e6f5ac1b29b 67 write( pwm, PCA9955_N_OF_PORTS + 1 );
nxp_ip 0:2e6f5ac1b29b 68 }
nxp_ip 0:2e6f5ac1b29b 69
nxp_ip 0:2e6f5ac1b29b 70 void PCA9955::set_all_intensity( char val, int iref ) {
nxp_ip 0:2e6f5ac1b29b 71 char c[ PCA9955_N_OF_PORTS ];
nxp_ip 0:2e6f5ac1b29b 72
nxp_ip 0:2e6f5ac1b29b 73 for ( int i = 0; i < PCA9955_N_OF_PORTS; i++ )
nxp_ip 0:2e6f5ac1b29b 74 c[ i ] = val;
nxp_ip 0:2e6f5ac1b29b 75
nxp_ip 0:2e6f5ac1b29b 76 set_all_intensity( c, iref );
nxp_ip 0:2e6f5ac1b29b 77 }
nxp_ip 0:2e6f5ac1b29b 78
nxp_ip 0:2e6f5ac1b29b 79 void PCA9955::get_all_intensity( char *p, int iref ) {
nxp_ip 0:2e6f5ac1b29b 80 read( (command_reg)(AUTO_INCREMENT | (iref ? IREF_REGISTER_START : PWM_REGISTER_START)), p, PCA9955_N_OF_PORTS );
nxp_ip 0:2e6f5ac1b29b 81 }
nxp_ip 0:2e6f5ac1b29b 82
nxp_ip 0:2e6f5ac1b29b 83 void PCA9955::operator=( int c ) {
nxp_ip 0:2e6f5ac1b29b 84 char a[ 1 + (PCA9955_N_OF_PORTS / 4) ] = { AUTO_INCREMENT | LEDOUT_REGISTER_START, 0x00, 0x00, 0x00, 0x00 };
nxp_ip 0:2e6f5ac1b29b 85 char out_val = 0x2;
nxp_ip 0:2e6f5ac1b29b 86
nxp_ip 0:2e6f5ac1b29b 87 for ( int i = 0; i < PCA9955_N_OF_PORTS; i++ )
nxp_ip 0:2e6f5ac1b29b 88 a[ (i / 4) + 1 ] |= (((c >> i) & 0x1) ? out_val : 0x0) << ((i % 4) << 1);
nxp_ip 0:2e6f5ac1b29b 89
nxp_ip 0:2e6f5ac1b29b 90 write( a, sizeof( a ) );
nxp_ip 0:2e6f5ac1b29b 91 }
nxp_ip 0:2e6f5ac1b29b 92
nxp_ip 0:2e6f5ac1b29b 93 unsigned short PCA9955::fault_test( void )
nxp_ip 0:2e6f5ac1b29b 94 {
nxp_ip 0:2e6f5ac1b29b 95 char mode2_reg;
nxp_ip 0:2e6f5ac1b29b 96
nxp_ip 0:2e6f5ac1b29b 97 #define FAULTTEST 0x40
nxp_ip 0:2e6f5ac1b29b 98
nxp_ip 0:2e6f5ac1b29b 99 mode2_reg = read( MODE2 );
nxp_ip 0:2e6f5ac1b29b 100 mode2_reg = 0;
nxp_ip 0:2e6f5ac1b29b 101 write( MODE2, mode2_reg | FAULTTEST );
nxp_ip 0:2e6f5ac1b29b 102
nxp_ip 0:2e6f5ac1b29b 103 while ( read( MODE2 ) & FAULTTEST )
nxp_ip 0:2e6f5ac1b29b 104 ;
nxp_ip 0:2e6f5ac1b29b 105
nxp_ip 0:2e6f5ac1b29b 106 return( ((unsigned short)(read( EFLAG1 )) << 8) | read( EFLAG0 ) );
nxp_ip 0:2e6f5ac1b29b 107 }
nxp_ip 0:2e6f5ac1b29b 108
nxp_ip 0:2e6f5ac1b29b 109 void PCA9955::write( char *data, int length ) {
nxp_ip 0:2e6f5ac1b29b 110 i2c.write( i2c_addr, data, length );
nxp_ip 0:2e6f5ac1b29b 111 }
nxp_ip 0:2e6f5ac1b29b 112
nxp_ip 0:2e6f5ac1b29b 113 void PCA9955::write( command_reg reg_addr, char data ) {
nxp_ip 0:2e6f5ac1b29b 114 char c[2];
nxp_ip 0:2e6f5ac1b29b 115
nxp_ip 0:2e6f5ac1b29b 116 c[0] = reg_addr;
nxp_ip 0:2e6f5ac1b29b 117 c[1] = data;
nxp_ip 0:2e6f5ac1b29b 118
nxp_ip 0:2e6f5ac1b29b 119 i2c.write( i2c_addr, c, 2 );
nxp_ip 0:2e6f5ac1b29b 120 }
nxp_ip 0:2e6f5ac1b29b 121
nxp_ip 0:2e6f5ac1b29b 122 void PCA9955::read( command_reg reg_addr, char *data, int length ) {
nxp_ip 0:2e6f5ac1b29b 123 i2c.write( i2c_addr, (char *)(&reg_addr), 1, true );
nxp_ip 0:2e6f5ac1b29b 124 i2c.read( i2c_addr, data, length );
nxp_ip 0:2e6f5ac1b29b 125 }
nxp_ip 0:2e6f5ac1b29b 126
nxp_ip 0:2e6f5ac1b29b 127 char PCA9955::read( command_reg reg_addr ) {
nxp_ip 0:2e6f5ac1b29b 128 i2c.write( i2c_addr, (char *)(&reg_addr), 1, true );
nxp_ip 0:2e6f5ac1b29b 129 i2c.read( i2c_addr, (char *)(&reg_addr), 1 );
nxp_ip 0:2e6f5ac1b29b 130
nxp_ip 0:2e6f5ac1b29b 131 return ( reg_addr );
nxp_ip 0:2e6f5ac1b29b 132 }
nxp_ip 0:2e6f5ac1b29b 133
nxp_ip 0:2e6f5ac1b29b 134 char PCA9955::init_array[] = {
nxp_ip 0:2e6f5ac1b29b 135 AUTO_INCREMENT | REGISTER_START, // Command
nxp_ip 0:2e6f5ac1b29b 136 0x00, 0x05, // MODE1, MODE2
nxp_ip 0:2e6f5ac1b29b 137 0xAA, 0xAA, 0xAA, 0xAA, // LEDOUT[3:0]
nxp_ip 0:2e6f5ac1b29b 138 0x80, 0x00, // GRPPWM, GRPFREQ
nxp_ip 0:2e6f5ac1b29b 139 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // PWM[7:0]
nxp_ip 0:2e6f5ac1b29b 140 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // PWM[15:8]
nxp_ip 0:2e6f5ac1b29b 141 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, // IREF[7:0]
nxp_ip 0:2e6f5ac1b29b 142 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, // IREF[15:8]
nxp_ip 0:2e6f5ac1b29b 143 0x08 // OFFSET: 1uS offsets
nxp_ip 0:2e6f5ac1b29b 144 };
nxp_ip 0:2e6f5ac1b29b 145