esp-open-rtos/extras/fast_i2c/i2c.h
2016-08-26 10:31:25 +02:00

102 lines
3.1 KiB
C

/*
* The MIT License (MIT)
*
* Copyright (c) 2015 Lilian Marazano (github.com/Zaltora)
* Based on Baoshi i2c library <mail(at)ba0sh1(dot)com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef __I2C_H__
#define __I2C_H__
#endif
#include <esp8266.h>
#include <espressif/esp_misc.h> // sdk_os_delay_us
#include <stdint.h>
#include <stdbool.h>
//#define _DELAY sdk_os_delay_us(1) // can up to 300kHz max
#define _DELAY for (volatile uint32_t __j = 3; __j > 0; __j--) // can up to 1.9MHz max at 160MHz clock
// if you want use an other API for GPIO or use GPIO16, change here
#define _SDA1 gpio_write(_sda_pin, 1)
#define _SDA0 gpio_write(_sda_pin, 0)
#define _SCL1 gpio_write(_scl_pin, 1)
#define _SCL0 gpio_write(_scl_pin, 0)
#define _SDAX gpio_read(_sda_pin)
#define _SCLX gpio_read(_scl_pin)
/**
* @brief Init I2C bus
* @param scl_pin SCL pin number
* @param sda_pin SDA pin number
*/
void i2c_init(uint8_t scl_pin, uint8_t sda_pin) ;
/**
* @brief Send data to I2C bus
* @param data Data to send
* @return true if ACK is received at end of sending. False if not ACK'ed
*/
uint8_t i2c_write(uint8_t data);
/**
* @brief Read data from I2C bus
* @param ack ACK (true) or NACK (false)
* @return Data read
*/
uint8_t i2c_read(uint8_t ack);
/**
* @brief Send I2C start bit
* @return true if start successfully. Otherwise the bus is busy
*/
uint8_t i2c_start(void);
/**
* @brief Send I2C stop bit
*/
void i2c_stop(void);
/**
* @brief Write multiple bytes to a device.
* @param slave_addr I2C slave device address
* @param buf Buffer to copy new data from
* @param len Number of bytes to write
* @return Status of operation (true = success)
*/
bool i2c_slave_write(uint8_t slave_addr, uint8_t *buf, uint16_t len);
/**
* @brief Read multiple bytes from a device register.
* @param slave_addr I2C slave device address
* @param data First register to read from
* @param buf Buffer to store read data in
* @param len Number of bytes to read
* @return Status of read operation (true = success)
*/
bool i2c_slave_read(uint8_t slave_addr, uint8_t data, uint8_t *buf, uint16_t len);