PokittoLib is the library needed for programming the Pokitto DIY game console (www.pokitto.com)
Diff: POKITTO_HW/SoftwareI2C.h
- Revision:
- 31:f4b9b85c7b62
diff -r 796f9611d2ac -r f4b9b85c7b62 POKITTO_HW/SoftwareI2C.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/POKITTO_HW/SoftwareI2C.h Tue Jan 30 10:41:47 2018 +0000 @@ -0,0 +1,146 @@ +/* + * mbed Library to use a software master i2c interface on any GPIO pins + * Copyright (c) 2012 Christopher Pepper + * Released under the MIT License: http://mbed.org/license/mit + */ + +#ifndef _SOFTWARE_I2C_H_ +#define _SOFTWARE_I2C_H_ + +#include "mbed.h" + +/** + * @brief SoftwareI2C class + */ + +class SoftwareI2C { +public: + SoftwareI2C(PinName sda, PinName scl); + ~SoftwareI2C(); + + void read(uint8_t device_address, uint8_t* data, uint8_t data_bytes); + void write(uint8_t device_address, uint8_t* data, uint8_t data_bytes); + void write(uint8_t device_address, uint8_t byte); + void randomRead(uint8_t device_address, uint8_t start_address, uint8_t* data, uint8_t data_bytes); + void randomWrite(uint8_t device_address, uint8_t start_address, uint8_t* data, uint8_t data_bytes); + void randomWrite(uint8_t device_address, uint8_t start_address, uint8_t byte); + + uint8_t read8(uint8_t device_address, uint8_t start_address); + uint16_t read16(uint8_t device_address, uint8_t start_address); + uint32_t read24(uint8_t device_address, uint8_t start_address); + uint32_t read32(uint8_t device_address, uint8_t start_address); + + void setDeviceAddress(uint8_t address){ + _device_address = address; + } + + void setFrequency(uint32_t frequency){ + _frequency_delay = 1000000 / frequency; + } + + inline void initialise() { + _scl.output(); + _sda.output(); + + _sda = 1; + _scl = 0; + wait_us(_frequency_delay); + + for ( int n = 0; n <= 3; ++n ) { + stop(); + } + } + +private: + inline void start() { + _sda.output(); + wait_us(_frequency_delay); + _scl = 1; + _sda = 1; + wait_us(_frequency_delay); + _sda = 0; + wait_us(_frequency_delay); + _scl = 0; + wait_us(_frequency_delay); + } + + inline void stop() { + _sda.output(); + wait_us(_frequency_delay); + _sda = 0; + wait_us(_frequency_delay); + _scl = 1; + wait_us(_frequency_delay); + _sda = 1; + } + + inline void putByte(uint8_t byte) { + _sda.output(); + for ( int n = 8; n > 0; --n) { + wait_us(_frequency_delay); + _sda = byte & (1 << (n-1)); + _scl = 1; + wait_us(_frequency_delay); + _scl = 0; + } + _sda = 1; + } + + inline uint8_t getByte() { + uint8_t byte = 0; + + _sda.input(); //release the data line + _sda.mode(OpenDrain); + + wait_us(_frequency_delay); + + for ( int n = 8; n > 0; --n ) { + _scl=1; //set clock high + wait_us(_frequency_delay); + byte |= _sda << (n-1); //read the bit + wait_us(_frequency_delay); + _scl=0; //set clock low + wait_us(_frequency_delay); + } + + _sda.output(); //take data line back + + return byte; + } + + inline void giveAck() { + _sda.output(); + wait_us(_frequency_delay); + _sda = 0; + _scl = 1; + wait_us(_frequency_delay); + _scl = 0; + _sda = 1; + + } + + inline bool getAck() { + _sda.output(); + _sda = 1; + _scl = 1; + _sda.input(); + _sda.mode(OpenDrain); + wait_us(_frequency_delay); + _scl = 0; + + if(_sda != 0){return false;} + + wait_us(_frequency_delay); + return true; + } + + DigitalInOut _sda; + DigitalInOut _scl; + + uint8_t _device_address; + uint32_t _frequency_delay; +}; + +#endif + +