savanni
/
avr
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Start on the i2c prototype

This commit is contained in:
Savanni D'Gerinel 2022-07-17 23:34:20 -04:00
parent 966ef20eca
commit 31a9bd76ba
2 changed files with 99 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

60
i2c/i2c.c Normal file
View File

@ -0,0 +1,60 @@
/*
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;
}
}

39
i2c/i2c.h Normal file
View File

@ -0,0 +1,39 @@
/*
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/>.
*/
#ifndef __I2C_H__
#define __I2C_H__
#include <base.h>
typedef enum {
ok,
nak
} i2c_error_e;
typedef struct {
dio_t sda;
dio_t clk;
} i2c_host_t;
typedef struct {
dio_t sda;
dio_t clk;
uint8_t addr;
}
void i2c_init_host(i2c_host_t *, i2c_error_e *);
void i2c_init_client(i2c_client_t *, i2c_error_e *);
void i2c_host_write(i2c_host_t *, uint8_t, uint8_t, size_t, i2c_error_e);
#endif