2.4 KiB
PCA9635
Arduino library for PCA9635 I2C 8 bit PWM LED driver
Description
This library is to control the I2C PCA9635 PWM extender. The 16 channels are independently configurable is steps of 1/256. this allows for better than 1% finetuning of the duty-cycle of the PWM signal.
interface
begin() initializes the library after startup. Mandatory.
begin(sda, scl) idem, ESP32 ESP8266 only. Library does not support multiple Wire instances (yet).
reset() resets the library to start up conditions.
setLedDriverMode(channel, mode) mode is 0..3 See datasheet for full details.
| LED mode | Value | Description |
|---|---|---|
| PCA9635_LEDOFF | 0x00 | led is 100% off, default @startup |
| PCA9635_LEDON | 0x01 | led is 100% on. |
| PCA9635_LEDPWM | 0x02 | set LED in PWM mode, 0..255 |
| PCA9635_LEDGRPPWM | 0x03 | add LED to the GRPPWM* |
* all leds in the group GRPPWM can be set to the same PWM value in one set. This is ideal to trigger e.g. multiple LEDS (servo's) at same time.
getLedDriverMode(channel) returns the current mode of the channel.
write1(channel, value) writes a single 8 bit PWM value.
write3(channel, R, G, B) writes three consecutive PWM registers.
writeN(channel, array, count) write count consecutive PWM registers. May return PCA9635_ERR_WRITE if array has too many elements (including channel as offset)
writeMode(reg, mode) configuration of one of the two configuration registers. check datasheet for details.
readMode(reg) reads back the configured mode, useful to add or remove a single flag (bit masking)
setGroupPWM(uint8_t value) sets all channels that are part of the PWM group to value.
getGroupPWM() get the current PWM setting of the group.
setGroupFREQ(value) see datasheet for details.
getGroupFREQ() returns the freq of the PWM group.
lastError() returns PCA9635_OK if all is OK, and other error codes otherwise.
| Error code | Value | Description |
|---|---|---|
| PCA9635_OK | 0x00 | Everything went well |
| PCA9635_ERROR | 0xFF | Generic error |
| PCA9635_ERR_WRITE | 0xFE | Tries to write more elements than PWM channels |
| PCA9635_ERR_CHAN | 0xFD | Channel out of range |
| PCA9635_ERR_MODE | 0xFC | Invalid mode |
| PCA9635_ERR_REG | 0xFB | Invalid register |
| PCA9635_ERR_I2C | 0xFA | PCA9635 I2C communication error |
Operation
See examples