avr_libraries/zh_avr_i2c
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

wip:

Browse Source
This commit is contained in:
Alexey Zholtikov
2025-08-09 12:28:35 +03:00
parent 851605cae3
commit 4547f6f510
2 changed files with 65 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
README.md
View File

@@ -1,3 +1,51 @@
# zh_avr_i2c
AVR library for I2C bus.
#include "avr/io.h"
#include "stdio.h"
#include "zh_avr_i2c.h"
#define BAUD_RATE 9600
#define BAUD_PRESCALE (F_CPU / 16 / BAUD_RATE - 1)
int usart(char byte, FILE *stream)
{
while ((UCSR0A & (1 << UDRE0)) == 0)
{
}
UDR0 = byte;
return 0;
}
FILE uart = FDEV_SETUP_STREAM(usart, NULL, _FDEV_SETUP_WRITE);
void i2c_example_task(void *pvParameters)
{
zh_avr_i2c_master_init(false);
avr_err_t err = zh_avr_i2c_master_probe(0x38, 100 / portTICK_PERIOD_MS);
switch (err)
{
case AVR_OK:
printf("Slave Answered.\n");
break;
case AVR_ERR_INVALID_RESPONSE:
printf("Slave Not Answer.\n");
break;
default:
printf("Bus Error.\n");
break;
}
vTaskDelete(NULL);
}
int main(void)
{
UBRR0H = (BAUD_PRESCALE >> 8);
UBRR0L = BAUD_PRESCALE;
UCSR0B = (1 << RXEN0) | (1 << TXEN0);
UCSR0C = (1 << UCSZ01) | (1 << UCSZ00);
stdout = &uart;
xTaskCreate(i2c_example_task, "i2c example task", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY, NULL);
vTaskStartScheduler();
return 0;
}

40
zh_avr_i2c.c
View File

@@ -11,7 +11,7 @@
#define I2C_COLLISION 0x04
#define I2C_BUS_FAIL 0x08
#define TWCR_START ((1 << TWINT) | (1 << TWEN) | (1 << TWIE))
#define I2C_START ((1 << TWINT) | (1 << TWEN) | (1 << TWIE))
#define I2C_MASTER_READ 1
#define I2C_MASTER_WRITE 0
@@ -47,7 +47,7 @@ avr_err_t zh_avr_i2c_master_probe(const uint8_t addr, TickType_t xTicksToWait)
{
_work_mode = MASTER_PR;
_target_i2c_address = addr;
TWCR = TWCR_START | (1 << TWSTA);
TWCR = I2C_START | (1 << TWSTA);
EventBits_t bits = xEventGroupWaitBits(_event_group_handle, I2C_OK | I2C_NACK | I2C_COLLISION | I2C_BUS_FAIL, pdTRUE, pdFALSE, xTicksToWait);
if (bits & I2C_OK)
{
@@ -106,12 +106,13 @@ uint8_t WorkIndex = 0; // Индекс лога
ISR(TWI_vect) // Прерывание TWI Тут наше все.
{
BaseType_t xHigherPriorityTaskWoken = pdFALSE;
switch (TWSR & 0xF8) // Отсекаем биты прескалера
{
case 0x00: // Bus error.
printf("00\n");
TWCR = TWCR_START | (1 << TWSTO);
xEventGroupSetBitsFromISR(_event_group_handle, I2C_BUS_FAIL, NULL);
TWCR = I2C_START | (1 << TWSTO);
xEventGroupSetBitsFromISR(_event_group_handle, I2C_BUS_FAIL, &xHigherPriorityTaskWoken);
break;
case 0x08: // A START condition has been transmitted.
printf("08\n");
@@ -125,7 +126,7 @@ ISR(TWI_vect) // Прерывание TWI Тут наше все.
break;
case MASTER_PR:
TWDR = (_target_i2c_address << 1) | I2C_MASTER_READ;
TWCR = TWCR_START;
TWCR = I2C_START;
break;
default:
break;
@@ -133,7 +134,7 @@ ISR(TWI_vect) // Прерывание TWI Тут наше все.
break;
case 0x10: // A repeated START condition has been transmitted.
printf("10\n");
TWCR = TWCR_START | (1 << TWSTO);
TWCR = I2C_START | (1 << TWSTO);
break;
case 0x18: // SLA+W has been transmitted. ACK has been received.
printf("18\n");
@@ -149,6 +150,8 @@ ISR(TWI_vect) // Прерывание TWI Тут наше все.
break;
case 0x38: // Arbitration lost in SLA+W or data bytes. Arbitration lost in SLA+R or NOT ACK bit.
printf("38\n");
TWCR = I2C_START | (1 << TWSTO);
xEventGroupSetBitsFromISR(_event_group_handle, I2C_COLLISION, &xHigherPriorityTaskWoken);
break;
case 0x40: // SLA+R has been transmitted. ACK has been received.
printf("40\n");
@@ -161,8 +164,8 @@ ISR(TWI_vect) // Прерывание TWI Тут наше все.
case MASTER_TX_RX:
break;
case MASTER_PR:
TWCR = TWCR_START | (1 << TWSTO);
xEventGroupSetBitsFromISR(_event_group_handle, I2C_OK, NULL);
TWCR = I2C_START | (1 << TWSTO);
xEventGroupSetBitsFromISR(_event_group_handle, I2C_OK, &xHigherPriorityTaskWoken);
break;
default:
break;
@@ -170,21 +173,8 @@ ISR(TWI_vect) // Прерывание TWI Тут наше все.
break;
case 0x48: // SLA+R has been transmitted. NOT ACK has been received.
printf("48\n");
switch (_work_mode)
{
case MASTER_TX:
break;
case MASTER_RX:
break;
case MASTER_TX_RX:
break;
case MASTER_PR:
TWCR = TWCR_START | (1 << TWSTO);
xEventGroupSetBitsFromISR(_event_group_handle, I2C_NACK, NULL);
break;
default:
break;
}
TWCR = I2C_START | (1 << TWSTO);
xEventGroupSetBitsFromISR(_event_group_handle, I2C_NACK, &xHigherPriorityTaskWoken);
break;
case 0x50: // Data byte has been received. ACK has been returned.
printf("50\n");
@@ -681,6 +671,10 @@ ISR(TWI_vect) // Прерывание TWI Тут наше все.
default:
break;
}
if (xHigherPriorityTaskWoken == pdTRUE)
{
portYIELD();
};
}
void DoNothing(void) // Функция пустышка, затыкать несуществующие ссылки