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-rwxr-xr-xdrivers/avr/i2c_master.c110
-rwxr-xr-xdrivers/avr/i2c_master.h2
-rwxr-xr-xdrivers/avr/i2c_slave.c134
-rwxr-xr-xdrivers/avr/i2c_slave.h10
4 files changed, 114 insertions, 142 deletions
diff --git a/drivers/avr/i2c_master.c b/drivers/avr/i2c_master.c
index 4e76e2e7c6..47c6f8e6c6 100755
--- a/drivers/avr/i2c_master.c
+++ b/drivers/avr/i2c_master.c
@@ -15,15 +15,15 @@
void i2c_init(void)
{
TWSR = 0; /* no prescaler */
- TWBR = (uint8_t)TWBR_val;
+ TWBR = (uint8_t)TWBR_val;
}
i2c_status_t i2c_start(uint8_t address, uint16_t timeout)
{
- // reset TWI control register
- TWCR = 0;
- // transmit START condition
- TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
+ // reset TWI control register
+ TWCR = 0;
+ // transmit START condition
+ TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
uint16_t timeout_timer = timer_read();
while( !(TWCR & (1<<TWINT)) ) {
@@ -32,13 +32,13 @@ i2c_status_t i2c_start(uint8_t address, uint16_t timeout)
}
}
- // check if the start condition was successfully transmitted
- if(((TW_STATUS & 0xF8) != TW_START) && ((TW_STATUS & 0xF8) != TW_REP_START)){ return I2C_STATUS_ERROR; }
+ // check if the start condition was successfully transmitted
+ if(((TW_STATUS & 0xF8) != TW_START) && ((TW_STATUS & 0xF8) != TW_REP_START)){ return I2C_STATUS_ERROR; }
- // load slave address into data register
- TWDR = address;
- // start transmission of address
- TWCR = (1<<TWINT) | (1<<TWEN);
+ // load slave address into data register
+ TWDR = address;
+ // start transmission of address
+ TWCR = (1<<TWINT) | (1<<TWEN);
timeout_timer = timer_read();
while( !(TWCR & (1<<TWINT)) ) {
@@ -47,19 +47,19 @@ i2c_status_t i2c_start(uint8_t address, uint16_t timeout)
}
}
- // 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 I2C_STATUS_ERROR;
+ // 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 I2C_STATUS_ERROR;
- return I2C_STATUS_SUCCESS;
+ return I2C_STATUS_SUCCESS;
}
i2c_status_t i2c_write(uint8_t data, uint16_t timeout)
{
- // load data into data register
- TWDR = data;
- // start transmission of data
- TWCR = (1<<TWINT) | (1<<TWEN);
+ // load data into data register
+ TWDR = data;
+ // start transmission of data
+ TWCR = (1<<TWINT) | (1<<TWEN);
uint16_t timeout_timer = timer_read();
while( !(TWCR & (1<<TWINT)) ) {
@@ -68,16 +68,16 @@ i2c_status_t i2c_write(uint8_t data, uint16_t timeout)
}
}
- if( (TW_STATUS & 0xF8) != TW_MT_DATA_ACK ){ return I2C_STATUS_ERROR; }
+ if( (TW_STATUS & 0xF8) != TW_MT_DATA_ACK ){ return I2C_STATUS_ERROR; }
- return I2C_STATUS_SUCCESS;
+ return I2C_STATUS_SUCCESS;
}
int16_t i2c_read_ack(uint16_t timeout)
{
- // start TWI module and acknowledge data after reception
- TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
+ // start TWI module and acknowledge data after reception
+ TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
uint16_t timeout_timer = timer_read();
while( !(TWCR & (1<<TWINT)) ) {
@@ -86,15 +86,15 @@ int16_t i2c_read_ack(uint16_t timeout)
}
}
- // return received data from TWDR
- return TWDR;
+ // return received data from TWDR
+ return TWDR;
}
int16_t i2c_read_nack(uint16_t timeout)
{
- // start receiving without acknowledging reception
- TWCR = (1<<TWINT) | (1<<TWEN);
+ // start receiving without acknowledging reception
+ TWCR = (1<<TWINT) | (1<<TWEN);
uint16_t timeout_timer = timer_read();
while( !(TWCR & (1<<TWINT)) ) {
@@ -103,39 +103,39 @@ int16_t i2c_read_nack(uint16_t timeout)
}
}
- // return received data from TWDR
- return TWDR;
+ // return received data from TWDR
+ return TWDR;
}
i2c_status_t i2c_transmit(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout)
{
i2c_status_t status = i2c_start(address | I2C_WRITE, timeout);
- if (status) return status;
+ if (status) return status;
- for (uint16_t i = 0; i < length; i++) {
- status = i2c_write(data[i], timeout);
+ for (uint16_t i = 0; i < length; i++) {
+ status = i2c_write(data[i], timeout);
if (status) return status;
- }
+ }
- status = i2c_stop(timeout);
+ status = i2c_stop(timeout);
if (status) return status;
- return I2C_STATUS_SUCCESS;
+ return I2C_STATUS_SUCCESS;
}
i2c_status_t i2c_receive(uint8_t address, uint8_t* data, uint16_t length, uint16_t timeout)
{
i2c_status_t status = i2c_start(address | I2C_READ, timeout);
- if (status) return status;
+ if (status) return status;
- for (uint16_t i = 0; i < (length-1); i++) {
+ for (uint16_t i = 0; i < (length-1); i++) {
status = i2c_read_ack(timeout);
if (status >= 0) {
data[i] = status;
} else {
return status;
}
- }
+ }
status = i2c_read_nack(timeout);
if (status >= 0 ) {
@@ -147,47 +147,47 @@ i2c_status_t i2c_receive(uint8_t address, uint8_t* data, uint16_t length, uint16
status = i2c_stop(timeout);
if (status) return status;
- return I2C_STATUS_SUCCESS;
+ return I2C_STATUS_SUCCESS;
}
i2c_status_t i2c_writeReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout)
{
i2c_status_t status = i2c_start(devaddr | 0x00, timeout);
- if (status) return status;
+ if (status) return status;
- status = i2c_write(regaddr, timeout);
+ status = i2c_write(regaddr, timeout);
if (status) return status;
- for (uint16_t i = 0; i < length; i++) {
+ for (uint16_t i = 0; i < length; i++) {
status = i2c_write(data[i], timeout);
- if (status) return status;
- }
+ if (status) return status;
+ }
- status = i2c_stop(timeout);
+ status = i2c_stop(timeout);
if (status) return status;
- return I2C_STATUS_SUCCESS;
+ return I2C_STATUS_SUCCESS;
}
i2c_status_t i2c_readReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout)
{
i2c_status_t status = i2c_start(devaddr, timeout);
- if (status) return status;
+ if (status) return status;
status = i2c_write(regaddr, timeout);
if (status) return status;
status = i2c_start(devaddr | 0x01, timeout);
- if (status) return status;
+ if (status) return status;
- for (uint16_t i = 0; i < (length-1); i++) {
- status = i2c_read_ack(timeout);
+ for (uint16_t i = 0; i < (length-1); i++) {
+ status = i2c_read_ack(timeout);
if (status >= 0) {
data[i] = status;
} else {
return status;
}
- }
+ }
status = i2c_read_nack(timeout);
if (status >= 0 ) {
@@ -199,13 +199,13 @@ i2c_status_t i2c_readReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16
status = i2c_stop(timeout);
if (status) return status;
- return I2C_STATUS_SUCCESS;
+ return I2C_STATUS_SUCCESS;
}
i2c_status_t i2c_stop(uint16_t timeout)
{
- // transmit STOP condition
- TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
+ // transmit STOP condition
+ TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
uint16_t timeout_timer = timer_read();
while(TWCR & (1<<TWSTO)) {
@@ -215,4 +215,4 @@ i2c_status_t i2c_stop(uint16_t timeout)
}
return I2C_STATUS_SUCCESS;
-}
+} \ No newline at end of file
diff --git a/drivers/avr/i2c_master.h b/drivers/avr/i2c_master.h
index cf93680be4..89c64599c5 100755
--- a/drivers/avr/i2c_master.h
+++ b/drivers/avr/i2c_master.h
@@ -28,4 +28,4 @@ i2c_status_t i2c_writeReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint1
i2c_status_t i2c_readReg(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout);
i2c_status_t i2c_stop(uint16_t timeout);
-#endif // I2C_MASTER_H
+#endif // I2C_MASTER_H \ No newline at end of file
diff --git a/drivers/avr/i2c_slave.c b/drivers/avr/i2c_slave.c
index 3edf85b12b..27696ca01a 100755
--- a/drivers/avr/i2c_slave.c
+++ b/drivers/avr/i2c_slave.c
@@ -5,96 +5,64 @@
#include <avr/io.h>
#include <util/twi.h>
#include <avr/interrupt.h>
+#include <stdbool.h>
#include "i2c_slave.h"
void i2c_init(uint8_t address){
- // load address into TWI address register
- TWAR = (address << 1);
- // set the TWCR to enable address matching and enable TWI, clear TWINT, enable TWI interrupt
- TWCR = (1<<TWIE) | (1<<TWEA) | (1<<TWINT) | (1<<TWEN);
+ // load address into TWI address register
+ TWAR = (address << 1);
+ // 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_stop(void){
- // clear acknowledge and enable bits
- TWCR &= ~( (1<<TWEA) | (1<<TWEN) );
+ // clear acknowledge and enable bits
+ TWCR &= ~((1 << TWEA) | (1 << TWEN));
}
ISR(TWI_vect){
-
- // temporary stores the received data
- uint8_t data;
-
- // own address has been acknowledged
- if( (TWSR & 0xF8) == TW_SR_SLA_ACK ){
- buffer_address = 0xFF;
- // clear TWI interrupt flag, prepare to receive next byte and acknowledge
- TWCR |= (1<<TWIE) | (1<<TWINT) | (1<<TWEA) | (1<<TWEN);
- }
- else if( (TWSR & 0xF8) == TW_SR_DATA_ACK ){ // data has been received in slave receiver mode
-
- // save the received byte inside data
- data = TWDR;
-
- // check wether an address has already been transmitted or not
- if(buffer_address == 0xFF){
-
- buffer_address = data;
-
- // clear TWI interrupt flag, prepare to receive next byte and acknowledge
- TWCR |= (1<<TWIE) | (1<<TWINT) | (1<<TWEA) | (1<<TWEN);
- }
- else{ // if a databyte has already been received
-
- // store the data at the current address
- rxbuffer[buffer_address] = data;
-
- // increment the buffer address
- buffer_address++;
-
- // if there is still enough space inside the buffer
- if(buffer_address < 0xFF){
- // clear TWI interrupt flag, prepare to receive next byte and acknowledge
- TWCR |= (1<<TWIE) | (1<<TWINT) | (1<<TWEA) | (1<<TWEN);
- }
- else{
- // Don't acknowledge
- TWCR &= ~(1<<TWEA);
- // clear TWI interrupt flag, prepare to receive last byte.
- TWCR |= (1<<TWIE) | (1<<TWINT) | (1<<TWEN);
- }
- }
- }
- else if( (TWSR & 0xF8) == TW_ST_DATA_ACK ){ // device has been addressed to be a transmitter
-
- // copy data from TWDR to the temporary memory
- data = TWDR;
-
- // if no buffer read address has been sent yet
- if( buffer_address == 0xFF ){
- buffer_address = data;
- }
-
- // copy the specified buffer address into the TWDR register for transmission
- TWDR = txbuffer[buffer_address];
- // increment buffer read address
- buffer_address++;
-
- // if there is another buffer address that can be sent
- if(buffer_address < 0xFF){
- // clear TWI interrupt flag, prepare to send next byte and receive acknowledge
- TWCR |= (1<<TWIE) | (1<<TWINT) | (1<<TWEA) | (1<<TWEN);
- }
- else{
- // Don't acknowledge
- TWCR &= ~(1<<TWEA);
- // clear TWI interrupt flag, prepare to receive last byte.
- TWCR |= (1<<TWIE) | (1<<TWINT) | (1<<TWEN);
- }
-
- }
- else{
- // if none of the above apply prepare TWI to be addressed again
- TWCR |= (1<<TWIE) | (1<<TWEA) | (1<<TWEN);
- }
-}
+ uint8_t ack = 1;
+ // temporary stores the received data
+ //uint8_t data;
+
+ 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 >= RX_BUFFER_SIZE){ // 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 {
+ rxbuffer[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 = txbuffer[buffer_address];
+ buffer_address++;
+ break;
+
+ case TW_BUS_ERROR:
+ // We got an error, reset i2c
+ TWCR = 0;
+ default:
+ break;
+ }
+
+ // Reset i2c state mahcine to be ready for next interrupt
+ TWCR |= (1 << TWIE) | (1 << TWINT) | (ack << TWEA) | (1 << TWEN);
+} \ No newline at end of file
diff --git a/drivers/avr/i2c_slave.h b/drivers/avr/i2c_slave.h
index 3fda7f8c09..1c3b9ecc00 100755
--- a/drivers/avr/i2c_slave.h
+++ b/drivers/avr/i2c_slave.h
@@ -8,12 +8,16 @@
#ifndef I2C_SLAVE_H
#define I2C_SLAVE_H
+#define TX_BUFFER_SIZE 30
+#define RX_BUFFER_SIZE 30
+
volatile uint8_t buffer_address;
-volatile uint8_t txbuffer[0xFF];
-volatile uint8_t rxbuffer[0xFF];
+static volatile bool slave_has_register_set = false;
+volatile uint8_t txbuffer[TX_BUFFER_SIZE];
+volatile uint8_t rxbuffer[RX_BUFFER_SIZE];
void i2c_init(uint8_t address);
void i2c_stop(void);
ISR(TWI_vect);
-#endif // I2C_SLAVE_H
+#endif // I2C_SLAVE_H \ No newline at end of file
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-16 04:21:12 +0000