avr/i2c/i2c.c

61 lines
1.9 KiB
C

/*
Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>
This file is part of Savanni's AVR library.
This AVR library 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 AVR library 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 AVR library. If not, see <https://www.gnu.org/licenses/>.
*/
#include <util/delay.h>
#include "i2c.h"
void i2c_init_host(i2c_host_t *bus, i2c_error_e *error) {
dio_set_direction(&bus->sda, LINE_OUT);
dio_set(&bus->sda, 1);
dio_set_direction(&bus->scl, LINE_OUT);
dio_set(&bus->scl, 1);
}
void i2c_init_client(i2c_client_t *bus, i2c_error_e *error) {
dio_set_direction(&bus->sda, LINE_IN);
dio_set_direction(&bus->scl, LINE_IN);
}
void i2c_host_write_packet(i2c_host_t *bus, uint8_t value, i2c_error_e *error) {
dio_set(&bus->sda, 0);
dio_set(&bus->scl, 0);
for (int i = 7; i >= 0; i--) {
dio_set(&bus->sda, value & _BV(i));
/*
if (value & _BV(i)) {
dio_set(&bus->sda, 1);
} else {
dio_set(&bus->sda, 0);
}
*/
dio_set(&bus->scl, 1);
dio_set(&bus->scl, 0);
}
dio_set_direction(&bus->scl, LINE_IN);
}
void i2c_host_write(i2c_host_t *bus, uint8_t address, uint8_t *data, size_t length, i2c_error_e *error) {
if (*error) return;
i2c_host_write_packet(bus, address << 1, error);
if (*error != ok) return;
for (int i = 0; i < length; i++) {
i2c_host_write_packet(bus, data[i], error);
if (*error != ok) return;
}
}