support for two wire via XWire library

Author: bombasticbob

cores/xmega/wiring.c

@@ -881,12 +881,23 @@ void init()
   // DISABLE TWI (specifically TWI interrupts)
   // -----------------------------------------
 
+#ifdef TWIC_CTRL
   TWIC_MASTER_CTRLA = 0;
   TWIC_SLAVE_CTRLA = 0;
-#if NUM_DIGITAL_PINS > 18 /* meaning there is a PORT E available */
+#endif // TWIC_CTRL
+#ifdef TWID_CTRL
+  TWID_MASTER_CTRLA = 0;
+  TWID_SLAVE_CTRLA = 0;
+#endif // TWID
+//#if NUM_DIGITAL_PINS > 18 /* meaning there is a PORT E available */
+#ifdef TWIE_CTRL
   TWIE_MASTER_CTRLA = 0;
   TWIE_SLAVE_CTRLA = 0;
-#endif // NUM_DIGITAL_PINS > 18
+#endif // TWIE_CTRL
+#ifdef TWIF_CTRL
+  TWIF_MASTER_CTRLA = 0;
+  TWIF_SLAVE_CTRLA = 0;
+#endif // TWIF
 
   // --------------------
   // DISABLE SERIAL PORTS

variants/xmega128a1/pins_arduino.h

@@ -96,7 +96,7 @@
 //
 #define DIGITAL_IO_PIN_SHIFT /* UNCOMMENT THIS to shift digital pin assignments for Arduino shield compatibility */
 
-//#define USE_AREF 0x2 /* see 28.16.3 in 'AU' manual - this is the REFCTRL bits for the reference select, AREF on PORTA (PA0) */
+//#define USE_AREF analogReference_PORTA0 /* see 28.16.3 in 'AU' manual - this is the REFCTRL bits for the reference select, AREF on PORTA (PA0) */
 
 #define NUM_DIGITAL_PINS            62
 
@@ -225,8 +225,27 @@
 // --------------------------------------------
 
 
-#define DEFAULT_TWI TWIC /* for now, later maybe TWIE? */
-#define TWIC_VECT_ENABLE /* use this to select the correct interrupt vectors */
+// TWI ports - default is TWIE
+#define DEFAULT_TWI TWIE
+
+// the XMega128a1u has four TWI ports
+#define TWI_PORT0 TWIE
+#define TWI_VECTOR_S0 TWIE_TWIS_vect
+#define TWI_VECTOR_M0 TWIE_TWIM_vect
+#define TWI_PORT1 TWIC
+#define TWI_VECTOR_S1 TWIC_TWIS_vect
+#define TWI_VECTOR_M1 TWIC_TWIM_vect
+#define TWI_PORT2 TWID
+#define TWI_VECTOR_S2 TWID_TWIS_vect
+#define TWI_VECTOR_M2 TWID_TWIM_vect
+#define TWI_PORT3 TWIF
+#define TWI_VECTOR_S3 TWIF_TWIS_vect
+#define TWI_VECTOR_M3 TWIF_TWIM_vect
+#define TWI_INTERFACE_COUNT 4
+
+
+// obsolete - consider removal in all of them
+//#define TWIC_VECT_ENABLE /* use this to select the correct interrupt vectors for default */
 
 // serial port 0
 #define SERIAL_0_PORT_NAME PORTD
@@ -348,12 +367,18 @@ static const uint8_t MOSI1 = 3;
 static const uint8_t MISO1 = 4;
 static const uint8_t SCK1  = 5;
 
-// default 2-wire on PE0,PE1 - TWIE  (for TWIC, you're on your own)
-// NOTE:  TWIE appears it may be broken, so switch to TWIC?
+// default 2-wire on PE0,PE1 - TWIE
+// NOTE:  this does NOT correspond to the mega2560, which uses 20 and 21 (need more remap work)
 static const uint8_t SDA = 14;
 static const uint8_t SCL = 15;
-
-// TODO:  alternate 2-wire ports
+static const uint8_t SDA0 = 14; // TWIE
+static const uint8_t SCL0 = 15;
+static const uint8_t SDA1 = 6;  // TWIC
+static const uint8_t SCL1 = 7;
+static const uint8_t SDA2 = 59;  // TWID
+static const uint8_t SCL2 = 60;
+static const uint8_t SDA3 = 22; // TWIF
+static const uint8_t SCL3 = 23;
 
 // keep track of the indices for port R since its control register
 // settings may be slightly different
@@ -382,11 +407,18 @@ static const uint8_t MOSI1 = 5;
 static const uint8_t MISO1 = 6;
 static const uint8_t SCK1  = 7;
 
-// default 2-wire on PE0,PE1 - TWIE  (for TWIC, you're on your own)
-// NOTE:  TWIE appears it may be broken, so switch to TWIC?
+// default 2-wire on PE0,PE1 - TWIE
 // NOTE:  this does NOT correspond to the mega2560, which uses 20 and 21 (need more remap work)
 static const uint8_t SDA = 16;
 static const uint8_t SCL = 17;
+static const uint8_t SDA0 = 16;
+static const uint8_t SCL0 = 17;
+static const uint8_t SDA1 = 8;
+static const uint8_t SCL1 = 9;
+static const uint8_t SDA2 = 0;
+static const uint8_t SCL2 = 1;
+static const uint8_t SDA3 = 24;
+static const uint8_t SCL3 = 25;
 
 // TODO:  alternate 2-wire ports TWIC?
 
@@ -522,25 +554,25 @@ const uint16_t PROGMEM port_to_input_PGM[] = {
 
 const uint16_t PROGMEM digital_pin_to_control_PGM[] = {
 #ifndef DIGITAL_IO_PIN_SHIFT
-  (uint16_t) &PORTD_PIN0CTRL,  // PD 0 ** 0 **
-  (uint16_t) &PORTD_PIN1CTRL,  // PD 1 ** 1 **
+  (uint16_t) &PORTD_PIN0CTRL,  // PD 0 ** 0 ** SDA2
+  (uint16_t) &PORTD_PIN1CTRL,  // PD 1 ** 1 ** SCL2
 #endif // DIGITAL_IO_PIN_SHIFT
   (uint16_t) &PORTD_PIN2CTRL,  // PD 2 ** 2 ** USARTD_RX     ASYNC
   (uint16_t) &PORTD_PIN3CTRL,  // PD 3 ** 3 ** USARTD_TX
   (uint16_t) &PORTD_PIN4CTRL,  // PD 4 ** 4 **
   (uint16_t) &PORTD_PIN5CTRL,  // PD 5 ** 5 **
   (uint16_t) &PORTD_PIN6CTRL,  // PD 6 ** 6 **
   (uint16_t) &PORTD_PIN7CTRL,  // PD 7 ** 7 **
-  (uint16_t) &PORTC_PIN0CTRL,  // PC 0 ** 8 **
-  (uint16_t) &PORTC_PIN1CTRL,  // PC 1 ** 9 **
+  (uint16_t) &PORTC_PIN0CTRL,  // PC 0 ** 8 ** SDA1
+  (uint16_t) &PORTC_PIN1CTRL,  // PC 1 ** 9 ** SCL1
   (uint16_t) &PORTC_PIN2CTRL,  // PC 2 ** 10 **              ASYNC
   (uint16_t) &PORTC_PIN3CTRL,  // PC 3 ** 11 **
   (uint16_t) &PORTC_PIN4CTRL,  // PC 4 ** 12 ** SPI_SS
   (uint16_t) &PORTC_PIN5CTRL,  // PC 5 ** 13 ** SPI_MOSI
   (uint16_t) &PORTC_PIN6CTRL,  // PC 6 ** 14 ** SPI_MISO
   (uint16_t) &PORTC_PIN7CTRL,  // PC 7 ** 15 ** SPI_SCK
-  (uint16_t) &PORTE_PIN0CTRL,  // PE 0 ** 16 ** SDA
-  (uint16_t) &PORTE_PIN1CTRL,  // PE 1 ** 17 ** SCL
+  (uint16_t) &PORTE_PIN0CTRL,  // PE 0 ** 16 ** SDA, SDA0
+  (uint16_t) &PORTE_PIN1CTRL,  // PE 1 ** 17 ** SCL, SCL0
   (uint16_t) &PORTE_PIN2CTRL,  // PE 2 ** 18 **              ASYNC
   (uint16_t) &PORTE_PIN3CTRL,  // PE 3 ** 19 **
 
@@ -549,8 +581,8 @@ const uint16_t PROGMEM digital_pin_to_control_PGM[] = {
   (uint16_t) &PORTE_PIN6CTRL,  // PE 3 ** 22 **
   (uint16_t) &PORTE_PIN7CTRL,  // PE 3 ** 23 **
 
-  (uint16_t) &PORTF_PIN0CTRL,  // PF 0 ** 24 **
-  (uint16_t) &PORTF_PIN1CTRL,  // PF 1 ** 25 **
+  (uint16_t) &PORTF_PIN0CTRL,  // PF 0 ** 24 ** SDA3
+  (uint16_t) &PORTF_PIN1CTRL,  // PF 1 ** 25 ** SCL3
   (uint16_t) &PORTF_PIN2CTRL,  // PF 2 ** 26 **              ASYNC
   (uint16_t) &PORTF_PIN3CTRL,  // PF 3 ** 27 **
   (uint16_t) &PORTF_PIN4CTRL,  // PF 4 ** 28 **
@@ -593,8 +625,8 @@ const uint16_t PROGMEM digital_pin_to_control_PGM[] = {
   (uint16_t) &PORTR_PIN0CTRL,  // PR 0 ** 60 **
   (uint16_t) &PORTR_PIN1CTRL,  // PR 1 ** 61 ** default LED
 #ifdef DIGITAL_IO_PIN_SHIFT
-  (uint16_t) &PORTD_PIN0CTRL,  // PD 0 ** the new 60 **
-  (uint16_t) &PORTD_PIN1CTRL,  // PD 1 ** the new 61 **
+  (uint16_t) &PORTD_PIN0CTRL,  // PD 0 ** the new 60 ** SDA2
+  (uint16_t) &PORTD_PIN1CTRL,  // PD 1 ** the new 61 ** SCL2
 #endif // DIGITAL_IO_PIN_SHIFT
   (uint16_t) &PORTA_PIN0CTRL,  // PA 0 ** 62 ** A0
   (uint16_t) &PORTA_PIN1CTRL,  // PA 1 ** 63 ** A1