Also merges tx/rx buffers, as only one is necessary.
#include "i2c_slave.h"
-void i2c_init(uint8_t address){
+volatile uint8_t i2c_slave_reg[I2C_SLAVE_REG_COUNT];
+
+static volatile uint8_t buffer_address;
+static volatile bool slave_has_register_set = false;
+
+void i2c_slave_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);
}
-void i2c_stop(void){
+void i2c_slave_stop(void){
// clear acknowledge and enable bits
TWCR &= ~((1 << TWEA) | (1 << TWEN));
}
ISR(TWI_vect){
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
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;
+ if (buffer_address >= I2C_SLAVE_REG_COUNT) { // 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;
+ i2c_slave_reg[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];
+ TWDR = i2c_slave_reg[buffer_address];
buffer_address++;
break;
break;
}
- // Reset i2c state mahcine to be ready for next interrupt
+ // Reset i2c state machine to be ready for next interrupt
TWCR |= (1 << TWIE) | (1 << TWINT) | (ack << TWEA) | (1 << TWEN);
}
\ No newline at end of file
#ifndef I2C_SLAVE_H
#define I2C_SLAVE_H
-#define TX_BUFFER_SIZE 30
-#define RX_BUFFER_SIZE 30
+#define I2C_SLAVE_REG_COUNT 30
-volatile uint8_t buffer_address;
-static volatile bool slave_has_register_set = false;
-volatile uint8_t txbuffer[TX_BUFFER_SIZE];
-volatile uint8_t rxbuffer[RX_BUFFER_SIZE];
+extern volatile uint8_t i2c_slave_reg[I2C_SLAVE_REG_COUNT];
-void i2c_init(uint8_t address);
-void i2c_stop(void);
-ISR(TWI_vect);
+void i2c_slave_init(uint8_t address);
+void i2c_slave_stop(void);
#endif // I2C_SLAVE_H
\ No newline at end of file
debouncing = false;
}
# endif
-
+
if (USB_DeviceState != DEVICE_STATE_Configured){
- txbuffer[1] = 0x55;
+ i2c_slave_reg[1] = 0x55;
for (uint8_t i = 0; i < MATRIX_ROWS; i++){
- txbuffer[i+2] = matrix[i]; //send matrix over i2c
+ i2c_slave_reg[i+2] = matrix[i]; //send matrix over i2c
}
}
-
+
matrix_scan_quantum();
return 1;
}
//this replases tmk code
void matrix_setup(void){
-
+
if (USB_DeviceState != DEVICE_STATE_Configured){
- i2c_init(SLAVE_I2C_ADDRESS); //setup address of slave i2c
+ i2c_slave_init(SLAVE_I2C_ADDRESS); //setup address of slave i2c
sei(); //enable interupts
}
}
\ No newline at end of file
debouncing = false;
}
# endif
-
+
if (USB_DeviceState != DEVICE_STATE_Configured){
- txbuffer[1] = 0x55;
+ i2c_slave_reg[1] = 0x55;
for (uint8_t i = 0; i < MATRIX_ROWS; i++){
- txbuffer[i+2] = matrix[i]; //send matrix over i2c
+ i2c_slave_reg[i+2] = matrix[i]; //send matrix over i2c
}
}
-
+
matrix_scan_quantum();
return 1;
}
//this replases tmk code
void matrix_setup(void){
-
+
if (USB_DeviceState != DEVICE_STATE_Configured){
- i2c_init(SLAVE_I2C_ADDRESS); //setup address of slave i2c
+ i2c_slave_init(SLAVE_I2C_ADDRESS); //setup address of slave i2c
sei(); //enable interupts
}
}
\ No newline at end of file
debouncing = false;
}
# endif
-
+
if (USB_DeviceState != DEVICE_STATE_Configured){
- txbuffer[1] = 0x55;
+ i2c_slave_reg[1] = 0x55;
for (uint8_t i = 0; i < MATRIX_ROWS; i++){
- txbuffer[i+2] = matrix[i]; //send matrix over i2c
+ i2c_slave_reg[i+2] = matrix[i]; //send matrix over i2c
}
}
-
+
matrix_scan_quantum();
return 1;
}
//this replases tmk code
void matrix_setup(void){
-
+
if (USB_DeviceState != DEVICE_STATE_Configured){
- i2c_init(SLAVE_I2C_ADDRESS); //setup address of slave i2c
+ i2c_slave_init(SLAVE_I2C_ADDRESS); //setup address of slave i2c
sei(); //enable interupts
}
}
\ No newline at end of file