X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=keyboards%2Fdeltasplit75%2Fi2c.c;h=084c890c405fa6f7ebfc1be7a699e3d120e5c482;hb=137456e5b1fa5d8bc88e6775a496013dec530037;hp=af806c75b6da4fd7346367375ac58fec7af84c91;hpb=9609a47c3e2050f252378386c0ce2b37b4c2aed8;p=qmk_firmware.git

diff --git a/keyboards/deltasplit75/i2c.c b/keyboards/deltasplit75/i2c.c
index af806c75b..084c890c4 100644
--- a/keyboards/deltasplit75/i2c.c
+++ b/keyboards/deltasplit75/i2c.c
@@ -1,162 +1,162 @@
-#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"
-
-#ifdef USE_I2C
-
-// 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);
-}
-#endif
+#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"
+
+#ifdef USE_I2C
+
+// 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);
+}
+#endif