From 96546c79c0e931c89e4ac60a154b669925d5d34d Mon Sep 17 00:00:00 2001
From: Jason <jagor@microsoft.com>
Date: Tue, 5 Jun 2018 12:43:20 -0700
Subject: Adding SX60 work by amnobis and configurator settings (#3122)

* Add SX60

* Add config maps and layouts as well as readmes.

* cleanup and fixes

* correct readme

* add missing closing commenty tag

* Changing includes to QMK_KEYBOARD_H

* Update settings.json

Remove config change that was added automatically by vscode.

* Update readme.md

fix readme formatting
---
 keyboards/sx60/twimaster.c | 207 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 207 insertions(+)
 create mode 100644 keyboards/sx60/twimaster.c

(limited to 'keyboards/sx60/twimaster.c')

diff --git a/keyboards/sx60/twimaster.c b/keyboards/sx60/twimaster.c
new file mode 100644
index 0000000000..30d8c24bf0
--- /dev/null
+++ b/keyboards/sx60/twimaster.c
@@ -0,0 +1,207 @@
+/*************************************************************************
+* Title:    I2C master library using hardware TWI interface
+* Author:   Peter Fleury <pfleury@gmx.ch>  http://jump.to/fleury
+* File:     $Id: twimaster.c,v 1.3 2005/07/02 11:14:21 Peter Exp $
+* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
+* Target:   any AVR device with hardware TWI
+* Usage:    API compatible with I2C Software Library i2cmaster.h
+**************************************************************************/
+#include <inttypes.h>
+#include <compat/twi.h>
+
+#include <i2cmaster.h>
+
+/* define CPU frequency in Hz here if not defined in Makefile */
+#ifndef F_CPU
+#define F_CPU 16000000UL
+#endif
+
+/* I2C clock in Hz */
+#define SCL_CLOCK  400000L
+
+
+/*************************************************************************
+ Initialization of the I2C bus interface. Need to be called only once
+*************************************************************************/
+void i2c_init(void)
+{
+  /* initialize TWI clock
+   * minimal values in Bit Rate Register (TWBR) and minimal Prescaler
+   * bits in the TWI Status Register should give us maximal possible
+   * I2C bus speed - about 444 kHz
+   *
+   * for more details, see 20.5.2 in ATmega16/32 secification
+   */
+
+  TWSR = 0;     /* no prescaler */
+  TWBR = 10;    /* must be >= 10 for stable operation */
+
+}/* i2c_init */
+
+
+/*************************************************************************
+  Issues a start condition and sends address and transfer direction.
+  return 0 = device accessible, 1= failed to access device
+*************************************************************************/
+unsigned char i2c_start(unsigned char address)
+{
+    uint8_t   twst;
+
+  /* send START condition */
+  TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
+ 
+  /* wait until transmission completed */
+  while(!(TWCR & (1<<TWINT)));
+
+  /* check value of TWI Status Register. Mask prescaler bits. */
+  twst = TW_STATUS & 0xF8;
+  if ( (twst != TW_START) && (twst != TW_REP_START)) return 1;
+
+  /* send device address */
+  TWDR = address;
+  TWCR = (1<<TWINT) | (1<<TWEN);
+
+  /* wail until transmission completed and ACK/NACK has been received */
+  while(!(TWCR & (1<<TWINT)));
+
+  /* check value of TWI Status Register. Mask prescaler bits. */
+  twst = TW_STATUS & 0xF8;
+  if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;
+
+  return 0;
+
+}/* i2c_start */
+
+
+/*************************************************************************
+ Issues a start condition and sends address and transfer direction.
+ If device is busy, use ack polling to wait until device is ready
+
+ Input:   address and transfer direction of I2C device
+*************************************************************************/
+void i2c_start_wait(unsigned char address)
+{
+    uint8_t   twst;
+
+
+    while ( 1 )
+    {
+      /* send START condition */
+      TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
+
+      /* wait until transmission completed */
+      while(!(TWCR & (1<<TWINT)));
+
+      /* check value of TWI Status Register. Mask prescaler bits. */
+      twst = TW_STATUS & 0xF8;
+      if ( (twst != TW_START) && (twst != TW_REP_START)) continue;
+
+      /* send device address */
+      TWDR = address;
+      TWCR = (1<<TWINT) | (1<<TWEN);
+
+      /* wail until transmission completed */
+      while(!(TWCR & (1<<TWINT)));
+
+      /* check value of TWI Status Register. Mask prescaler bits. */
+      twst = TW_STATUS & 0xF8;
+      if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
+      {
+          /* device busy, send stop condition to terminate write operation */
+          TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
+
+          /* wait until stop condition is executed and bus released */
+          while(TWCR & (1<<TWSTO));
+
+          continue;
+      }
+      
+      break;
+     }
+
+}/* i2c_start_wait */
+
+
+/*************************************************************************
+ Issues a repeated start condition and sends address and transfer direction
+
+ Input:   address and transfer direction of I2C device
+
+ Return:  0 device accessible
+          1 failed to access device
+*************************************************************************/
+unsigned char i2c_rep_start(unsigned char address)
+{
+    return i2c_start( address );
+
+}/* i2c_rep_start */
+
+
+/*************************************************************************
+ Terminates the data transfer and releases the I2C bus
+*************************************************************************/
+void i2c_stop(void)
+{
+  /* send stop condition */
+  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
+
+  /* wait until stop condition is executed and bus released */
+  while(TWCR & (1<<TWSTO));
+
+}/* i2c_stop */
+
+
+/*************************************************************************
+  Send one byte to I2C device
+
+  Input:    byte to be transfered
+  Return:   0 write successful
+            1 write failed
+*************************************************************************/
+unsigned char i2c_write( unsigned char data )
+{
+    uint8_t   twst;
+
+  /* send data to the previously addressed device */
+  TWDR = data;
+  TWCR = (1<<TWINT) | (1<<TWEN);
+
+  /* wait until transmission completed */
+  while(!(TWCR & (1<<TWINT)));
+
+  /* check value of TWI Status Register. Mask prescaler bits */
+  twst = TW_STATUS & 0xF8;
+  if( twst != TW_MT_DATA_ACK) return 1;
+  return 0;
+
+}/* i2c_write */
+
+
+/*************************************************************************
+ Read one byte from the I2C device, request more data from device
+
+ Return:  byte read from I2C device
+*************************************************************************/
+unsigned char i2c_readAck(void)
+{
+  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
+  while(!(TWCR & (1<<TWINT)));
+
+  return TWDR;
+
+}/* i2c_readAck */
+
+
+/*************************************************************************
+ Read one byte from the I2C device, read is followed by a stop condition
+
+ Return:  byte read from I2C device
+*************************************************************************/
+unsigned char i2c_readNak(void)
+{
+  TWCR = (1<<TWINT) | (1<<TWEN);
+  while(!(TWCR & (1<<TWINT)));
+
+  return TWDR;
+
+}/* i2c_readNak */
-- 
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