diff options
Diffstat (limited to 'drivers/avr/i2c_master.c')
| -rw-r--r-- | drivers/avr/i2c_master.c | 224 | 
1 files changed, 0 insertions, 224 deletions
| diff --git a/drivers/avr/i2c_master.c b/drivers/avr/i2c_master.c deleted file mode 100644 index b1e4885298..0000000000 --- a/drivers/avr/i2c_master.c +++ /dev/null @@ -1,224 +0,0 @@ -/*  Copyright (C) 2019 Elia Ritterbusch - + - *  This program is free software: you can redistribute it and/or modify - *  it under the terms of the GNU General Public License as published by - *  the Free Software Foundation, either version 3 of the License, or - *  (at your option) any later version. - * - *  This program is distributed in the hope that it will be useful, - *  but WITHOUT ANY WARRANTY; without even the implied warranty of - *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the - *  GNU General Public License for more details. - * - *  You should have received a copy of the GNU General Public License - *  along with this program.  If not, see <https://www.gnu.org/licenses/>. - */ -/* Library made by: g4lvanix - * GitHub repository: https://github.com/g4lvanix/I2C-master-lib - */ - -#include <avr/io.h> -#include <util/twi.h> - -#include "i2c_master.h" -#include "timer.h" -#include "wait.h" - -#ifndef F_SCL -#    define F_SCL 400000UL  // SCL frequency -#endif - -#define TWBR_val (((F_CPU / F_SCL) - 16) / 2) - -void i2c_init(void) { -    TWSR = 0; /* no prescaler */ -    TWBR = (uint8_t)TWBR_val; - -#ifdef __AVR_ATmega32A__ -    // set pull-up resistors on I2C bus pins -    PORTC |= 0b11; - -    // enable TWI (two-wire interface) -    TWCR |= (1 << TWEN); - -    // enable TWI interrupt and slave address ACK -    TWCR |= (1 << TWIE); -    TWCR |= (1 << TWEA); -#endif -} - -i2c_status_t i2c_start(uint8_t address, uint16_t timeout) { -    // reset TWI control register -    TWCR = 0; -    // transmit START condition -    TWCR = (1 << TWINT) | (1 << TWSTA) | (1 << TWEN); - -    uint16_t timeout_timer = timer_read(); -    while (!(TWCR & (1 << TWINT))) { -        if ((timeout != I2C_TIMEOUT_INFINITE) && ((timer_read() - timeout_timer) >= timeout)) { -            return I2C_STATUS_TIMEOUT; -        } -    } - -    // check if the start condition was successfully transmitted -    if (((TW_STATUS & 0xF8) != TW_START) && ((TW_STATUS & 0xF8) != TW_REP_START)) { -        return I2C_STATUS_ERROR; -    } - -    // load slave address into data register -    TWDR = address; -    // start transmission of address -    TWCR = (1 << TWINT) | (1 << TWEN); - -    timeout_timer = timer_read(); -    while (!(TWCR & (1 << TWINT))) { -        if ((timeout != I2C_TIMEOUT_INFINITE) && ((timer_read() - timeout_timer) >= timeout)) { -            return I2C_STATUS_TIMEOUT; -        } -    } - -    // check if the device has acknowledged the READ / WRITE mode -    uint8_t twst = TW_STATUS & 0xF8; -    if ((twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK)) { -        return I2C_STATUS_ERROR; -    } - -    return I2C_STATUS_SUCCESS; -} - -i2c_status_t i2c_write(uint8_t data, uint16_t timeout) { -    // load data into data register -    TWDR = data; -    // start transmission of data -    TWCR = (1 << TWINT) | (1 << TWEN); - -    uint16_t timeout_timer = timer_read(); -    while (!(TWCR & (1 << TWINT))) { -        if ((timeout != I2C_TIMEOUT_INFINITE) && ((timer_read() - timeout_timer) >= timeout)) { -            return I2C_STATUS_TIMEOUT; -        } -    } - -    if ((TW_STATUS & 0xF8) != TW_MT_DATA_ACK) { -        return I2C_STATUS_ERROR; -    } - -    return I2C_STATUS_SUCCESS; -} - -int16_t i2c_read_ack(uint16_t timeout) { -    // start TWI module and acknowledge data after reception -    TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWEA); - -    uint16_t timeout_timer = timer_read(); -    while (!(TWCR & (1 << TWINT))) { -        if ((timeout != I2C_TIMEOUT_INFINITE) && ((timer_read() - timeout_timer) >= timeout)) { -            return I2C_STATUS_TIMEOUT; -        } -    } - -    // return received data from TWDR -    return TWDR; -} - -int16_t i2c_read_nack(uint16_t timeout) { -    // start receiving without acknowledging reception -    TWCR = (1 << TWINT) | (1 << TWEN); - -    uint16_t timeout_timer = timer_read(); -    while (!(TWCR & (1 << TWINT))) { -        if ((timeout != I2C_TIMEOUT_INFINITE) && ((timer_read() - timeout_timer) >= timeout)) { -            return I2C_STATUS_TIMEOUT; -        } -    } - -    // return received data from TWDR -    return TWDR; -} - -i2c_status_t i2c_transmit(uint8_t address, const uint8_t* data, uint16_t length, uint16_t timeout) { -    i2c_status_t status = i2c_start(address | I2C_WRITE, timeout); - -    for (uint16_t i = 0; i < length && status >= 0; i++) { -        status = i2c_write(data[i], timeout); -    } - -    i2c_stop(); - -    return status; -} - -i2c_status_t i2c_receive(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout) { -    i2c_status_t status = i2c_start(address | I2C_READ, timeout); - -    for (uint16_t i = 0; i < (length - 1) && status >= 0; i++) { -        status = i2c_read_ack(timeout); -        if (status >= 0) { -            data[i] = status; -        } -    } - -    if (status >= 0) { -        status = i2c_read_nack(timeout); -        if (status >= 0) { -            data[(length - 1)] = status; -        } -    } - -    i2c_stop(); - -    return (status < 0) ? status : I2C_STATUS_SUCCESS; -} - -i2c_status_t i2c_writeReg(uint8_t devaddr, uint8_t regaddr, const uint8_t* data, uint16_t length, uint16_t timeout) { -    i2c_status_t status = i2c_start(devaddr | 0x00, timeout); -    if (status >= 0) { -        status = i2c_write(regaddr, timeout); - -        for (uint16_t i = 0; i < length && status >= 0; i++) { -            status = i2c_write(data[i], timeout); -        } -    } - -    i2c_stop(); - -    return status; -} - -i2c_status_t i2c_readReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout) { -    i2c_status_t status = i2c_start(devaddr, timeout); -    if (status < 0) { -        goto error; -    } - -    status = i2c_write(regaddr, timeout); -    if (status < 0) { -        goto error; -    } - -    status = i2c_start(devaddr | 0x01, timeout); - -    for (uint16_t i = 0; i < (length - 1) && status >= 0; i++) { -        status = i2c_read_ack(timeout); -        if (status >= 0) { -            data[i] = status; -        } -    } - -    if (status >= 0) { -        status = i2c_read_nack(timeout); -        if (status >= 0) { -            data[(length - 1)] = status; -        } -    } - -error: -    i2c_stop(); - -    return (status < 0) ? status : I2C_STATUS_SUCCESS; -} - -void i2c_stop(void) { -    // transmit STOP condition -    TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO); -} | 
