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authoryiancar <yiangosyiangou@cytanet.com.cy>2018-07-18 19:55:57 +0300
committerJack Humbert <jack.humb@gmail.com>2018-07-18 12:55:57 -0400
commit72fd49b1468d6bbfa59e1c6334866d7aa34f31c1 (patch)
treed9d5d7a66eebd37765e2ff103e09ed57d787eae9 /drivers/avr/i2c_slave.c
parent7e9a7af672ab226cc57f05f362d6b1e965ac56e6 (diff)
downloadqmk_firmware-72fd49b1468d6bbfa59e1c6334866d7aa34f31c1.tar.gz
qmk_firmware-72fd49b1468d6bbfa59e1c6334866d7aa34f31c1.zip
DC01 keyboard addition (#3428)
* DC01 initial commit - Addition of directories - Left readme * Initial commit of left half * Initial files for right half * arrow * i2c adjustments * I2C slave and DC01 refractoring - Cleaned up state machine of I2C slave driver - Modified DC01 left to use already pressent I2C master driver - Modified DC01 matrixes * Fixed tabs to spaces * Addition of Numpad * Add keymaps - Orthopad keymap for numpad module - Numpad keymap for numpad module - ISO, ANSI and HHKB version of keymap for right module * Minor matrix.c fixes * Update Readmes
Diffstat (limited to 'drivers/avr/i2c_slave.c')
-rwxr-xr-xdrivers/avr/i2c_slave.c134
1 files changed, 51 insertions, 83 deletions
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