I2C Piezo Haptic Driver with Integrated Boost Converter and Digital Front End
drv2665.cpp
- Committer:
- akashvibhute
- Date:
- 2016-05-25
- Revision:
- 0:b85fd3fdfcfa
- Child:
- 1:e2c726c628dc
File content as of revision 0:b85fd3fdfcfa:
/** * DRV2665 library * * @author Akash Vibhute * @author < akash . roboticist [at] gmail . com > * @version 0.1 * @date May/24/2016 */ #include "drv2665.h" #define M_PI 3.14159265358979 DRV2665_DIGITAL::DRV2665_DIGITAL( PinName sda, PinName scl ):i2c_(sda, scl) { i2c_addr = DRV2665_I2C_ADDRESS << 1; wait_ms(2); //wait 2ms for i2c bus } void DRV2665_DIGITAL::init(uint8_t output_gain, uint8_t idle_timeout) { write(DRV2665_CTRL_2, 0); //clear standby write(DRV2665_CTRL_1, (DRV2665_DIGITAL_IN | output_gain)); //set mode digital, set gain write(DRV2665_CTRL_2, idle_timeout); //set timeout period } void DRV2665_DIGITAL::reset() { write(DRV2665_CTRL_2, DRV2665_DEV_RST); } void DRV2665_DIGITAL::outputWave(int8_t waveform[], uint8_t length) { if(fifo_check()) { for(int i=0; i<length; i++) { write(DRV2665_FIFO, waveform[i]); wait_us(5); } } else return; } void DRV2665_DIGITAL::outputSine(uint16_t hz) { int8_t waveform_byte; uint16_t length; //in the linux driver example, a 41 byte waveform plays back at 8kHz //wavelength 41 -> wave time 125us -> frequency 8kHz //hence per byte sampling time = 125us / 41 = 3.04878049 //ie 41 bytes :: 8kHz -> 328 bytes :: 1000Hz //calculations done here are from this factor length = (1000 * 328) / hz; /* //If the above assumption is incorrect, it could be that the DRV plays //anything in its FIFO at a fix rate of 8ksps in that case, it would mean //a per byte play time of 125us, ie for a 100byte wavelength -> a playback //time of 1.25ms (800Hz) //So, 100B :: 800Hz -> 100*800B :: 1Hz //For 'n' Hz :: (100*800/n) B length = (100 * 800) / hz; */ for(int i=0; i<length; i++) { waveform_byte = (uint8_t)(102.0 * sin(2*M_PI*i/(length-1))); //102 is the max +ve / -ve value, typecasting in uint8 turns -ve values into 2's complement required by the driver write(DRV2665_FIFO, waveform_byte); wait_us(5); while(!fifo_check()) wait_us(5); } } bool DRV2665_DIGITAL::fifo_check() { uint8_t reply; reply = read(DRV2665_STATUS); if((reply & 0x01) == 0) return(true); else return(false); } void DRV2665_DIGITAL::en_override(bool en) { write(DRV2665_CTRL_2, DRV2665_BOOST_EN); } uint8_t DRV2665_DIGITAL::read(char reg) { //Create a temporary buffer char buff[2]; //Select the register i2c_.write(i2c_addr, ®, 1, true); //Read the 16-bit register i2c_.read(i2c_addr, buff, 2); //Return the combined 16-bit value return (buff[0] << 8) | buff[1]; } void DRV2665_DIGITAL::write(char reg, uint8_t data) { //Create a temporary buffer char buff[2]; //Load the register address and 16-bit data buff[0] = reg; buff[1] = data; //Write the data i2c_.write(i2c_addr, buff, 2); }