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Diffstat (limited to 'drivers/avr/i2c_slave.c')
-rw-r--r--drivers/avr/i2c_slave.c86
1 files changed, 0 insertions, 86 deletions
diff --git a/drivers/avr/i2c_slave.c b/drivers/avr/i2c_slave.c
deleted file mode 100644
index 62a378165a..0000000000
--- a/drivers/avr/i2c_slave.c
+++ /dev/null
@@ -1,86 +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-slave-lib
- */
-
-#include <avr/io.h>
-#include <util/twi.h>
-#include <avr/interrupt.h>
-#include <stdbool.h>
-
-#include "i2c_slave.h"
-
-volatile uint8_t i2c_slave_reg[I2C_SLAVE_REG_COUNT];
-
-static volatile uint8_t buffer_address;
-static volatile bool slave_has_register_set = false;
-
-void i2c_slave_init(uint8_t address) {
- // load address into TWI address register
- TWAR = address;
- // set the TWCR to enable address matching and enable TWI, clear TWINT, enable TWI interrupt
- TWCR = (1 << TWIE) | (1 << TWEA) | (1 << TWINT) | (1 << TWEN);
-}
-
-void i2c_slave_stop(void) {
- // clear acknowledge and enable bits
- TWCR &= ~((1 << TWEA) | (1 << TWEN));
-}
-
-ISR(TWI_vect) {
- uint8_t ack = 1;
-
- switch (TW_STATUS) {
- case TW_SR_SLA_ACK:
- // The device is now a slave receiver
- slave_has_register_set = false;
- break;
-
- case TW_SR_DATA_ACK:
- // This device is a slave receiver and has received data
- // First byte is the location then the bytes will be writen in buffer with auto-incriment
- if (!slave_has_register_set) {
- buffer_address = TWDR;
-
- if (buffer_address >= I2C_SLAVE_REG_COUNT) { // address out of bounds dont ack
- ack = 0;
- buffer_address = 0;
- }
- slave_has_register_set = true; // address has been receaved now fill in buffer
- } else {
- i2c_slave_reg[buffer_address] = TWDR;
- buffer_address++;
- }
- break;
-
- case TW_ST_SLA_ACK:
- case TW_ST_DATA_ACK:
- // This device is a slave transmitter and master has requested data
- TWDR = i2c_slave_reg[buffer_address];
- buffer_address++;
- break;
-
- case TW_BUS_ERROR:
- // We got an error, reset i2c
- TWCR = 0;
- default:
- break;
- }
-
- // Reset i2c state machine to be ready for next interrupt
- TWCR |= (1 << TWIE) | (1 << TWINT) | (ack << TWEA) | (1 << TWEN);
-}