PCA TEST
Dependencies: mbed
Fork of PCA9685PWM by
PCA9685.cpp
- Committer:
- niklasjakob
- Date:
- 2017-06-12
- Revision:
- 2:3e7e063a6538
- Parent:
- 0:c7f4744deec3
File content as of revision 2:3e7e063a6538:
#include "PCA9685.h" #include "mbed.h" PCA9685::PCA9685(PinName sda, PinName scl, int addr) : i2c(sda, scl), _i2caddr(addr) {} void PCA9685::begin(void) { reset(); } void PCA9685::frequencyI2C(int freq) { i2c.frequency(freq); } void PCA9685::write8(uint8_t address, uint8_t data) { char cmd[2]; cmd[0] = address; cmd[1] = data; i2c.write(_i2caddr, cmd, 2); } char PCA9685::read8(char address) { i2c.write(_i2caddr, &address, 1); char rtn; i2c.read(_i2caddr, &rtn, 1); return rtn; } void PCA9685::reset(void) { write8(PCA9685_MODE1, 0x0); } void PCA9685::setPrescale(uint8_t prescale) { uint8_t oldmode = read8(PCA9685_MODE1); uint8_t newmode = (oldmode&0x7F) | 0x10; // sleep write8(PCA9685_MODE1, newmode); // go to sleep wait_ms(5); write8(PCA9685_PRESCALE, prescale); // set the prescaler write8(PCA9685_MODE1, oldmode); wait_ms(5); write8(PCA9685_MODE1, oldmode | 0xa1); } void PCA9685::setPWMFreq(float freq) { float prescaleval = 25000000; prescaleval /= 4096; prescaleval /= freq; uint8_t prescale = floor(prescaleval + 0.5) - 1; setPrescale(prescale); } void PCA9685::setPWM(uint8_t num, uint16_t on, uint16_t off) { char cmd[5]; cmd[0] = LED0_ON_L + 4 * num; cmd[1] = on; cmd[2] = on >> 8; cmd[3] = off; cmd[4] = off >> 8; i2c.write(_i2caddr, cmd, 5); }