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Diffstat (limited to 'keyboards/pearl/i2c.c')
-rw-r--r-- | keyboards/pearl/i2c.c | 106 |
1 files changed, 0 insertions, 106 deletions
diff --git a/keyboards/pearl/i2c.c b/keyboards/pearl/i2c.c deleted file mode 100644 index a4f9521352..0000000000 --- a/keyboards/pearl/i2c.c +++ /dev/null @@ -1,106 +0,0 @@ -/* -Copyright 2016 Luiz Ribeiro <luizribeiro@gmail.com> - -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 2 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 <http://www.gnu.org/licenses/>. -*/ - -// Please do not modify this file - -#include <avr/io.h> -#include <util/twi.h> - -#include "i2c.h" - -void i2c_set_bitrate(uint16_t bitrate_khz) { - uint8_t bitrate_div = ((F_CPU / 1000l) / bitrate_khz); - if (bitrate_div >= 16) { - bitrate_div = (bitrate_div - 16) / 2; - } - TWBR = bitrate_div; -} - -void i2c_init(void) { - // set pull-up resistors on I2C bus pins - PORTC |= 0b11; - - i2c_set_bitrate(400); - - // enable TWI (two-wire interface) - TWCR |= (1 << TWEN); - - // enable TWI interrupt and slave address ACK - TWCR |= (1 << TWIE); - TWCR |= (1 << TWEA); -} - -uint8_t i2c_start(uint8_t address) { - // reset TWI control register - TWCR = 0; - - // begin transmission and wait for it to end - TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN); - while (!(TWCR & (1<<TWINT))); - - // check if the start condition was successfully transmitted - if ((TWSR & 0xF8) != TW_START) { - return 1; - } - - // transmit address and wait - TWDR = address; - TWCR = (1<<TWINT) | (1<<TWEN); - while (!(TWCR & (1<<TWINT))); - - // 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 1; - } - - return 0; -} - -void i2c_stop(void) { - TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO); -} - -uint8_t i2c_write(uint8_t data) { - TWDR = data; - - // transmit data and wait - TWCR = (1<<TWINT) | (1<<TWEN); - while (!(TWCR & (1<<TWINT))); - - if ((TWSR & 0xF8) != TW_MT_DATA_ACK) { - return 1; - } - - return 0; -} - -uint8_t i2c_send(uint8_t address, uint8_t *data, uint16_t length) { - if (i2c_start(address)) { - return 1; - } - - for (uint16_t i = 0; i < length; i++) { - if (i2c_write(data[i])) { - return 1; - } - } - - i2c_stop(); - - return 0; -} |