i2c working

keyboards/lets-split/Makefile → keyboards/lets_split/Makefile

@@ -1,4 +1,6 @@
-
+SRC += matrix.c \
+	   i2c.c \
+	   split_util.c
 
 # MCU name
 #MCU = at90usb1287
@@ -68,6 +70,8 @@ RGBLIGHT_ENABLE ?= no        # Enable WS2812 RGB underlight.  Do not enable this
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE ?= no    # Breathing sleep LED during USB suspend
 
+CUSTOM_MATRIX = yes
+
 ifndef QUANTUM_DIR
 	include ../../Makefile
 endif

keyboards/lets-split/config.h → keyboards/lets_split/config.h

@@ -29,12 +29,18 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define DESCRIPTION     A split keyboard for the cheap makers
 
 /* key matrix size */
-#define MATRIX_ROWS 4
+#define MATRIX_ROWS 8
 #define MATRIX_COLS 6
 
-#define MATRIX_ROW_PINS { B5, B4, E6, D7, }
+// wiring of each half
+#define MATRIX_ROW_PINS { B5, B4, E6, D7 }
 #define MATRIX_COL_PINS { F4, F5, F6, F7, B1, B3 }
 
+#define USE_I2C
+
+// #define I2C_MASTER_LEFT
+#define I2C_MASTER_RIGHT
+
 /* COL2ROW or ROW2COL */
 #define DIODE_DIRECTION COL2ROW
 

keyboards/lets_split/i2c.c

@@ -0,0 +1,159 @@
+#include <util/twi.h>
+#include <avr/io.h>
+#include <stdlib.h>
+#include <avr/interrupt.h>
+#include <util/twi.h>
+#include <stdbool.h>
+#include "i2c.h"
+
+// Limits the amount of we wait for any one i2c transaction.
+// Since were running SCL line 100kHz (=> 10μs/bit), and each transactions is
+// 9 bits, a single transaction will take around 90μs to complete.
+//
+// (F_CPU/SCL_CLOCK)  =>  # of μC cycles to transfer a bit
+// poll loop takes at least 8 clock cycles to execute
+#define I2C_LOOP_TIMEOUT (9+1)*(F_CPU/SCL_CLOCK)/8
+
+#define BUFFER_POS_INC() (slave_buffer_pos = (slave_buffer_pos+1)%SLAVE_BUFFER_SIZE)
+
+volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
+
+static volatile uint8_t slave_buffer_pos;
+static volatile bool slave_has_register_set = false;
+
+// Wait for an i2c operation to finish
+inline static
+void i2c_delay(void) {
+  uint16_t lim = 0;
+  while(!(TWCR & (1<<TWINT)) && lim < I2C_LOOP_TIMEOUT)
+    lim++;
+
+  // easier way, but will wait slightly longer
+  // _delay_us(100);
+}
+
+// Setup twi to run at 100kHz
+void i2c_master_init(void) {
+  // no prescaler
+  TWSR = 0;
+  // Set TWI clock frequency to SCL_CLOCK. Need TWBR>10.
+  // Check datasheets for more info.
+  TWBR = ((F_CPU/SCL_CLOCK)-16)/2;
+}
+
+// Start a transaction with the given i2c slave address. The direction of the
+// transfer is set with I2C_READ and I2C_WRITE.
+// returns: 0 => success
+//          1 => error
+uint8_t i2c_master_start(uint8_t address) {
+  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTA);
+
+  i2c_delay();
+
+  // check that we started successfully
+  if ( (TW_STATUS != TW_START) && (TW_STATUS != TW_REP_START))
+    return 1;
+
+  TWDR = address;
+  TWCR = (1<<TWINT) | (1<<TWEN);
+
+  i2c_delay();
+
+  if ( (TW_STATUS != TW_MT_SLA_ACK) && (TW_STATUS != TW_MR_SLA_ACK) )
+    return 1; // slave did not acknowledge
+  else
+    return 0; // success
+}
+
+
+// Finish the i2c transaction.
+void i2c_master_stop(void) {
+  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
+
+  uint16_t lim = 0;
+  while(!(TWCR & (1<<TWSTO)) && lim < I2C_LOOP_TIMEOUT)
+    lim++;
+}
+
+// Write one byte to the i2c slave.
+// returns 0 => slave ACK
+//         1 => slave NACK
+uint8_t i2c_master_write(uint8_t data) {
+  TWDR = data;
+  TWCR = (1<<TWINT) | (1<<TWEN);
+
+  i2c_delay();
+
+  // check if the slave acknowledged us
+  return (TW_STATUS == TW_MT_DATA_ACK) ? 0 : 1;
+}
+
+// Read one byte from the i2c slave. If ack=1 the slave is acknowledged,
+// if ack=0 the acknowledge bit is not set.
+// returns: byte read from i2c device
+uint8_t i2c_master_read(int ack) {
+  TWCR = (1<<TWINT) | (1<<TWEN) | (ack<<TWEA);
+
+  i2c_delay();
+  return TWDR;
+}
+
+void i2c_reset_state(void) {
+  TWCR = 0;
+}
+
+void i2c_slave_init(uint8_t address) {
+  TWAR = address << 0; // slave i2c address
+  // TWEN  - twi enable
+  // TWEA  - enable address acknowledgement
+  // TWINT - twi interrupt flag
+  // TWIE  - enable the twi interrupt
+  TWCR = (1<<TWIE) | (1<<TWEA) | (1<<TWINT) | (1<<TWEN);
+}
+
+ISR(TWI_vect);
+
+ISR(TWI_vect) {
+  uint8_t ack = 1;
+  switch(TW_STATUS) {
+    case TW_SR_SLA_ACK:
+      // this device has been addressed as a slave receiver
+      slave_has_register_set = false;
+      break;
+
+    case TW_SR_DATA_ACK:
+      // this device has received data as a slave receiver
+      // The first byte that we receive in this transaction sets the location
+      // of the read/write location of the slaves memory that it exposes over
+      // i2c.  After that, bytes will be written at slave_buffer_pos, incrementing
+      // slave_buffer_pos after each write.
+      if(!slave_has_register_set) {
+        slave_buffer_pos = TWDR;
+        // don't acknowledge the master if this memory loctaion is out of bounds
+        if ( slave_buffer_pos >= SLAVE_BUFFER_SIZE ) {
+          ack = 0;
+          slave_buffer_pos = 0;
+        }
+        slave_has_register_set = true;
+      } else {
+        i2c_slave_buffer[slave_buffer_pos] = TWDR;
+        BUFFER_POS_INC();
+      }
+      break;
+
+    case TW_ST_SLA_ACK:
+    case TW_ST_DATA_ACK:
+      // master has addressed this device as a slave transmitter and is
+      // requesting data.
+      TWDR = i2c_slave_buffer[slave_buffer_pos];
+      BUFFER_POS_INC();
+      break;
+
+    case TW_BUS_ERROR: // something went wrong, reset twi state
+      TWCR = 0;
+    default:
+      break;
+  }
+  // Reset everything, so we are ready for the next TWI interrupt
+  TWCR |= (1<<TWIE) | (1<<TWINT) | (ack<<TWEA) | (1<<TWEN);
+}

keyboards/lets_split/i2c.h

@@ -0,0 +1,31 @@
+#ifndef I2C_H
+#define I2C_H
+
+#include <stdint.h>
+
+#ifndef F_CPU
+#define F_CPU 16000000UL
+#endif
+
+#define I2C_READ 1
+#define I2C_WRITE 0
+
+#define I2C_ACK 1
+#define I2C_NACK 0
+
+#define SLAVE_BUFFER_SIZE 0x10
+
+// i2c SCL clock frequency
+#define SCL_CLOCK  100000L
+
+extern volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
+
+void i2c_master_init(void);
+uint8_t i2c_master_start(uint8_t address);
+void i2c_master_stop(void);
+uint8_t i2c_master_write(uint8_t data);
+uint8_t i2c_master_read(int);
+void i2c_reset_state(void);
+void i2c_slave_init(uint8_t address);
+
+#endif

keyboards/lets-split/keymaps/default/keymap.c → keyboards/lets_split/keymaps/default/keymap.c

@@ -1,4 +1,4 @@
-#include "lets-split.h"
+#include "lets_split.h"
 #include "action_layer.h"
 
 #define BASE 0
@@ -14,12 +14,12 @@ enum preonic_keycodes {
 
 const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
 
-[BASE] = {
-  {KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T     },
-  {KC_ESC,  KC_A,    KC_S,    KC_D,    KC_F,    KC_G     },
-  {KC_LSFT, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B     },
-  {KC_IDK,  KC_LCTL, KC_LALT, KC_LGUI, KC_SPC,  PM_RESET }
-}
+[BASE] = KEYMAP(
+  KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,        KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_BSPC, \
+  KC_ESC,  KC_A,    KC_S,    KC_D,    KC_F,    KC_G,        KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT, \
+  KC_LSFT, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,        KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, KC_ENT, \
+  KC_IDK,  KC_LCTL, KC_LALT, KC_LGUI, PM_RESET,KC_SPC,      KC_SPC,  PM_RESET,KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT \
+)
 
 };
 

keyboards/lets-split/lets-split.c → keyboards/lets_split/lets_split.c

@@ -1,4 +1,4 @@
-#include "lets-split.h"
+#include "lets_split.h"
 
 #ifdef AUDIO_ENABLE
     float tone_startup[][2] = SONG(STARTUP_SOUND);
@@ -12,13 +12,13 @@ void matrix_init_kb(void) {
         PLAY_NOTE_ARRAY(tone_startup, false, 0);
     #endif
 
-    // green led on
-    DDRD |= (1<<5);
-    PORTD &= ~(1<<5);
+    // // green led on
+    // DDRD |= (1<<5);
+    // PORTD &= ~(1<<5);
 
-    // orange led on
-    DDRB |= (1<<0);
-    PORTB &= ~(1<<0);
+    // // orange led on
+    // DDRB |= (1<<0);
+    // PORTB &= ~(1<<0);
 
 	matrix_init_user();
 };

keyboards/lets_split/lets_split.h

@@ -0,0 +1,21 @@
+#include "quantum.h"
+#include <avr/wdt.h>
+
+void promicro_bootloader_jmp(bool program);
+
+#define KEYMAP( \
+	k00, k01, k02, k03, k04, k05, k40, k41, k42, k43, k44, k45, \
+	k10, k11, k12, k13, k14, k15, k50, k51, k52, k53, k54, k55, \
+	k20, k21, k22, k23, k24, k25, k60, k61, k62, k63, k64, k65, \
+	k30, k31, k32, k33, k34, k35, k70, k71, k72, k73, k74, k75 \
+	) \
+	{ \
+		{ k00, k01, k02, k03, k04, k05 }, \
+		{ k10, k11, k12, k13, k14, k15 }, \
+		{ k20, k21, k22, k23, k24, k25 }, \
+		{ k30, k31, k32, k33, k34, k35 }, \
+		{ k40, k41, k42, k43, k44, k45 }, \
+		{ k50, k51, k52, k53, k54, k55 }, \
+		{ k60, k61, k62, k63, k64, k65 }, \
+		{ k70, k71, k72, k73, k74, k75 } \
+	}