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Polishing i2c related source

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Imbus 2024-03-24 00:00:32 +01:00
parent 15cd7b52ab
commit bdb94eb75b
3 changed files with 41 additions and 54 deletions
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42
i2c.c
View file

@ -1,8 +1,11 @@
#include <avr/io.h>
#include <util/delay.h>
#include "i2c.h"
void initI2C() {
#include <avr/io.h>
#include <util/delay.h>
#include <util/twi.h>
#include <stdint.h>
void I2C_init() {
// Set the prescaler to 1
TWSR &= ~(1 << TWPS0);
TWSR &= ~(1 << TWPS1);
@ -10,35 +13,58 @@ void initI2C() {
TWBR = ((F_CPU / 100000) - 16) / 2;
}
void I2C_start() {
uint8_t I2C_start(uint8_t addr) {
// Send the start condition
TWCR = (1 << TWINT) | (1 << TWSTA) | (1 << TWEN);
// Wait for the start condition to be sent
while (!(TWCR & (1 << TWINT)))
;
// Load the address of the slave device
TWDR = addr;
// Clear the TWINT bit to start the transmission
TWCR = (1 << TWINT) | (1 << TWEN);
// Wait for the address to be sent
while (!(TWCR & (1 << TWINT)))
;
// Get the status of the transmission
uint8_t status = TWSR & 0xF8;
// Return true if the slave acknowledged the address
return (status == TW_MT_SLA_ACK || status == TW_MR_SLA_ACK);
}
void I2C_stop() {
// Send the stop condition
TWCR = (1 << TWINT) | (1 << TWSTO) | (1 << TWEN);
// Wait for the stop condition to be sent
while (TWCR & (1 << TWSTO));
while (TWCR & (1 << TWSTO))
;
}
void I2C_write(uint8_t data) {
uint8_t I2C_write(uint8_t data) {
// Load the data into the data register
TWDR = data;
// Start transmission of data
TWCR = (1 << TWINT) | (1 << TWEN);
// Wait for the data to be sent
while (!(TWCR & (1 << TWINT)));
while (!(TWCR & (1 << TWINT)))
;
// Return true if the data was sent
return (TWSR & 0xF8) == TW_MT_DATA_ACK;
}
uint8_t I2C_read(uint8_t ack) {
// Enable TWI, generate ACK (if ack = 1) and clear TWI interrupt flag
TWCR = (1 << TWINT) | (1 << TWEN) | (ack << TWEA);
// Wait until TWI finish its current job (read operation)
while (!(TWCR & (1 << TWINT)));
while (!(TWCR & (1 << TWINT)))
;
// Return received data
return TWDR;
}

7
i2c.h
View file

@ -1,7 +1,8 @@
#pragma once
#include <stdint.h>
void initI2C();
void I2C_start();
void I2C_init();
uint8_t I2C_start(uint8_t addr);
void I2C_stop();
void I2C_write(uint8_t data);
uint8_t I2C_write(uint8_t data);
uint8_t I2C_read(uint8_t ack);

46
main.c
View file

@ -5,42 +5,16 @@
* need pull-up resistors for the I2C lines.
*/
#define LED_PIN PB5 // Define the pin connected to the LED
#include <avr/io.h>
#include <util/delay.h>
#include <math.h>
#define LED_PIN PB5 // Define the pin connected to the LED
#define TEMP_SENSOR_ADDR 0x48
#define TEMP_REG_ADDR 0x00
#include "MPU6050.h"
#include "i2c.h"
#include "uart.h"
float readTemperature() {
uint16_t temperature;
// Send start condition
I2C_start();
// Send device address with write operation
I2C_write((TEMP_SENSOR_ADDR << 1) | 0);
// Send temperature register address
I2C_write(0x00);
// Repeat start
I2C_start();
// Send device address with read operation
I2C_write((TEMP_SENSOR_ADDR << 1) | 1);
// Read temperature data MSB
temperature = (uint16_t)(I2C_read(1)) << 8;
// Read temperature data LSB
temperature |= I2C_read(0);
// Send stop condition
I2C_stop();
// Convert raw data to temperature in Celsius
return (float)temperature * 0.0625;
}
void blink() {
// Set the LED pin as output
DDRB |= (1 << LED_PIN);
@ -59,7 +33,6 @@ void blink() {
}
int main(void) {
// initI2C();
initUART();
while(1) {
@ -67,18 +40,5 @@ int main(void) {
_delay_ms(1000);
}
// float temperature;
// while (1) {
// temperature = readTemperature();
// // Print temperature over UART
// UART_println("Temperature: ");
// UART_transmit((uint8_t)(temperature / 10.0) + '0');
// UART_transmit((uint8_t)fmod(temperature, 10.0) + '0');
// UART_println(" °C");
// _delay_ms(1000); // Delay for 1 second
// }
// return 0;
return 0;
}