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test

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This commit is contained in:
Bruno Rybársky
2025-05-05 09:02:25 +02:00
parent 9bb4d59e11
commit df55dcfe4c
4 changed files with 452 additions and 299 deletions
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136
i2c.c
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@@ -1,74 +1,84 @@
/*
* I2C_Slave_C_File.c
*
*/
*/
#include "i2c.h"
void I2C_Slave_Init(uint8_t slave_address)
{
TWAR = slave_address; /* Assign address in TWI address register */
TWCR = (1<<TWEN) | (1<<TWEA) | (1<<TWINT); /* Enable TWI, Enable ack generation, clear TWI interrupt */
void I2C_Slave_Init(uint8_t slave_address) {
TWAR = slave_address << 1; /* Assign address in TWI address register (shifted left by 1) */
TWCR = (1<<TWEN) | (1<<TWEA) | (1<<TWIE) | (1<<TWINT); /* Enable TWI, Enable ack generation, enable interrupt, clear interrupt flag */
}
int8_t I2C_Slave_Listen()
{
while(1)
{
uint8_t status; /* Declare variable */
while (!(TWCR & (1<<TWINT))); /* Wait to be addressed */
status = TWSR & 0xF8; /* Read TWI status register with masking lower three bits */
if (status == 0x60 || status == 0x68) /* Check weather own SLA+W received & ack returned (TWEA = 1) */
return 0; /* If yes then return 0 to indicate ack returned */
if (status == 0xA8 || status == 0xB0) /* Check weather own SLA+R received & ack returned (TWEA = 1) */
return 1; /* If yes then return 1 to indicate ack returned */
if (status == 0x70 || status == 0x78) /* Check weather general call received & ack returned (TWEA = 1) */
return 2; /* If yes then return 2 to indicate ack returned */
else
continue; /* Else continue */
}
int8_t I2C_Slave_Listen() {
while(1) {
uint8_t status; /* Declare variable */
while (!(TWCR & (1<<TWINT))); /* Wait to be addressed */
status = TWSR & 0xF8; /* Read TWI status register with masking lower three bits */
if (status == 0x60 || status == 0x68) /* Check weather own SLA+W received & ack returned (TWEA = 1) */
return 0; /* If yes then return 0 to indicate ack returned */
if (status == 0xA8 || status == 0xB0) /* Check weather own SLA+R received & ack returned (TWEA = 1) */
return 1; /* If yes then return 1 to indicate ack returned */
if (status == 0x70 || status == 0x78) /* Check weather general call received & ack returned (TWEA = 1) */
return 2; /* If yes then return 2 to indicate ack returned */
else
continue; /* Else continue */
}
}
int8_t I2C_Slave_Transmit(char data)
{
uint8_t status;
TWDR = data; /* Write data to TWDR to be transmitted */
TWCR = (1<<TWEN)|(1<<TWINT)|(1<<TWEA); /* Enable TWI and clear interrupt flag */
while (!(TWCR & (1<<TWINT))); /* Wait until TWI finish its current job (Write operation) */
status = TWSR & 0xF8; /* Read TWI status register with masking lower three bits */
if (status == 0xA0) /* Check weather STOP/REPEATED START received */
{
TWCR |= (1<<TWINT); /* If yes then clear interrupt flag & return -1 */
return -1;
}
if (status == 0xB8) /* Check weather data transmitted & ack received */
return 0; /* If yes then return 0 */
if (status == 0xC0) /* Check weather data transmitted & nack received */
{
TWCR |= (1<<TWINT); /* If yes then clear interrupt flag & return -2 */
return -2;
}
if (status == 0xC8) /* If last data byte transmitted with ack received TWEA = 0 */
return -3; /* If yes then return -3 */
else /* else return -4 */
return -4;
int8_t I2C_Slave_Transmit(char data) {
uint8_t status;
TWDR = data; /* Write data to TWDR to be transmitted */
TWCR = (1<<TWEN) | (1<<TWINT) | (1<<TWEA); /* Enable TWI and clear interrupt flag */
while (!(TWCR & (1<<TWINT))); /* Wait until TWI finish its current job (Write operation) */
status = TWSR & 0xF8; /* Read TWI status register with masking lower three bits */
if (status == 0xA0) /* Check weather STOP/REPEATED START received */
{
TWCR |= (1<<TWINT); /* If yes then clear interrupt flag & return -1 */
return -1;
}
if (status == 0xB8) /* Check weather data transmitted & ack received */
return 0; /* If yes then return 0 */
if (status == 0xC0) /* Check weather data transmitted & nack received */
{
TWCR |= (1<<TWINT); /* If yes then clear interrupt flag & return -2 */
return -2;
}
if (status == 0xC8) /* If last data byte transmitted with ack received TWEA = 0 */
return -3; /* If yes then return -3 */
else /* else return -4 */
return -4;
}
char I2C_Slave_Receive()
{
uint8_t status; /* Declare variable */
TWCR=(1<<TWEN)|(1<<TWEA)|(1<<TWINT); /* Enable TWI, generation of ack and clear interrupt flag */
while (!(TWCR & (1<<TWINT))); /* Wait until TWI finish its current job (read operation) */
status = TWSR & 0xF8; /* Read TWI status register with masking lower three bits */
if (status == 0x80 || status == 0x90) /* Check weather data received & ack returned (TWEA = 1) */
return TWDR; /* If yes then return received data */
if (status == 0x88 || status == 0x98) /* Check weather data received, nack returned and switched to not addressed slave mode */
return TWDR; /* If yes then return received data */
if (status == 0xA0) /* Check weather STOP/REPEATED START received */
{
TWCR |= (1<<TWINT); /* If yes then clear interrupt flag & return 0 */
return -1;
}
else
return -2; /* Else return 1 */
}
char I2C_Slave_Receive() {
uint8_t status; /* Declare variable */
TWCR = (1<<TWEN) | (1<<TWEA) | (1<<TWINT); /* Enable TWI, generation of ack and clear interrupt flag */
while (!(TWCR & (1<<TWINT))); /* Wait until TWI finish its current job (read operation) */
status = TWSR & 0xF8; /* Read TWI status register with masking lower three bits */
if (status == 0x80 || status == 0x90) /* Check weather data received & ack returned (TWEA = 1) */
return TWDR; /* If yes then return received data */
if (status == 0x88 || status == 0x98) /* Check weather data received, nack returned and switched to not addressed slave mode */
return TWDR; /* If yes then return received data */
if (status == 0xA0) /* Check weather STOP/REPEATED START received */
{
TWCR |= (1<<TWINT); /* If yes then clear interrupt flag & return -1 */
return -1;
}
else
return -2; /* Else return -2 */
}