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Diffstat (limited to 'drivers/avr/i2c_master.c')
-rw-r--r--drivers/avr/i2c_master.c241
1 files changed, 0 insertions, 241 deletions
diff --git a/drivers/avr/i2c_master.c b/drivers/avr/i2c_master.c
deleted file mode 100644
index 2773e00778..0000000000
--- a/drivers/avr/i2c_master.c
+++ /dev/null
@@ -1,241 +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
-
-#ifndef I2C_START_RETRY_COUNT
-# define I2C_START_RETRY_COUNT 20
-#endif // I2C_START_RETRY_COUNT
-
-#define TWBR_val (((F_CPU / F_SCL) - 16) / 2)
-
-#define MAX(X, Y) ((X) > (Y) ? (X) : (Y))
-
-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
-}
-
-static i2c_status_t i2c_start_impl(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_start(uint8_t address, uint16_t timeout) {
- // Retry i2c_start_impl a bunch times in case the remote side has interrupts disabled.
- uint16_t timeout_timer = timer_read();
- uint16_t time_slice = MAX(1, (timeout == (I2C_TIMEOUT_INFINITE)) ? 5 : (timeout / (I2C_START_RETRY_COUNT))); // if it's infinite, wait 1ms between attempts, otherwise split up the entire timeout into the number of retries
- i2c_status_t status;
- do {
- status = i2c_start_impl(address, time_slice);
- } while ((status < 0) && ((timeout == I2C_TIMEOUT_INFINITE) || (timer_elapsed(timeout_timer) < timeout)));
- return status;
-}
-
-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);
-}
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