1 /* Copyright 2018 Jason Williams (Wilba)
3 * This program is free software: you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation, either version 2 of the License, or
6 * (at your option) any later version.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 #include "is31fl3218.h"
17 #include "i2c_master.h"
19 // This is the full 8-bit address
20 #define ISSI_ADDRESS 0b10101000
22 // These are the register addresses
23 #define ISSI_REG_SHUTDOWN 0x00
24 #define ISSI_REG_PWM 0x01
25 #define ISSI_REG_CONTROL 0x13
26 #define ISSI_REG_UPDATE 0x16
27 #define ISSI_REG_RESET 0x17
29 // Default timeout if no I2C response
30 #define ISSI_TIMEOUT 100
32 // Reusable buffer for transfers
33 uint8_t g_twi_transfer_buffer[20];
35 // IS31FL3218 has 18 PWM outputs and a fixed I2C address, so no chaining.
36 // If used as RGB LED driver, LEDs are assigned RGB,RGB,RGB,RGB,RGB,RGB
37 uint8_t g_pwm_buffer[18];
38 bool g_pwm_buffer_update_required = false;
40 void IS31FL3218_write_register( uint8_t reg, uint8_t data )
42 g_twi_transfer_buffer[0] = reg;
43 g_twi_transfer_buffer[1] = data;
44 i2c_transmit( ISSI_ADDRESS, g_twi_transfer_buffer, 2, ISSI_TIMEOUT);
47 void IS31FL3218_write_pwm_buffer( uint8_t *pwm_buffer )
49 g_twi_transfer_buffer[0] = ISSI_REG_PWM;
50 for ( int i=0; i<18; i++ ) {
51 g_twi_transfer_buffer[1+i] = pwm_buffer[i];
54 i2c_transmit( ISSI_ADDRESS, g_twi_transfer_buffer, 19, ISSI_TIMEOUT);
57 void IS31FL3218_init(void)
59 // In case we ever want to reinitialize (?)
60 IS31FL3218_write_register( ISSI_REG_RESET, 0x00 );
62 // Turn off software shutdown
63 IS31FL3218_write_register( ISSI_REG_SHUTDOWN, 0x01 );
65 // Set all PWM values to zero
66 for ( uint8_t i = 0; i < 18; i++ ) {
67 IS31FL3218_write_register( ISSI_REG_PWM+i, 0x00 );
70 // Enable all channels
71 for ( uint8_t i = 0; i < 3; i++ ) {
72 IS31FL3218_write_register( ISSI_REG_CONTROL+i, 0b00111111 );
75 // Load PWM registers and LED Control register data
76 IS31FL3218_write_register( ISSI_REG_UPDATE, 0x01 );
79 void IS31FL3218_set_color( int index, uint8_t red, uint8_t green, uint8_t blue )
81 g_pwm_buffer[index * 3 + 0] = red;
82 g_pwm_buffer[index * 3 + 1] = green;
83 g_pwm_buffer[index * 3 + 2] = blue;
84 g_pwm_buffer_update_required = true;
87 void IS31FL3218_set_color_all( uint8_t red, uint8_t green, uint8_t blue )
89 for ( int i = 0; i < 6; i++ ) {
90 IS31FL3218_set_color( i, red, green, blue );
94 void IS31FL3218_update_pwm_buffers(void)
96 if ( g_pwm_buffer_update_required ) {
97 IS31FL3218_write_pwm_buffer( g_pwm_buffer );
98 // Load PWM registers and LED Control register data
99 IS31FL3218_write_register( ISSI_REG_UPDATE, 0x01 );
101 g_pwm_buffer_update_required = false;