diff options
Diffstat (limited to 'drivers/avr/i2c_slave.c')
| -rw-r--r-- | drivers/avr/i2c_slave.c | 86 | 
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); -} | 
