Displays distance to start location on OLED screen.

Dependencies:   mbed

Revision:
0:972874f31c98
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/u8g_com_arduino_hw_usart_spi.c	Wed Mar 07 12:49:14 2018 +0000
@@ -0,0 +1,160 @@
+/*
+  
+  u8g_com_arduino_hw_usart_spi.c
+
+  Universal 8bit Graphics Library
+  
+  Copyright (c) 2011, olikraus@gmail.com
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without modification, 
+  are permitted provided that the following conditions are met:
+
+  * Redistributions of source code must retain the above copyright notice, this list 
+    of conditions and the following disclaimer.
+    
+  * Redistributions in binary form must reproduce the above copyright notice, this 
+    list of conditions and the following disclaimer in the documentation and/or other 
+    materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
+  CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
+  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
+  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
+  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 
+  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
+  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
+  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
+  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+
+  SPI Clock Cycle Type
+  
+  SSD1351	  50ns		20 MHz
+  SSD1322	300ns		  3.3 MHz
+  SSD1327	300ns
+  SSD1306	300ns
+  ST7565		400ns 		  2.5 MHz
+  ST7920		400ns
+
+*/
+
+#include "u8g.h"
+
+#if defined(ARDUINO)
+
+#if defined(__AVR_ATmega32U4__ )
+
+#include <avr/interrupt.h>
+#include <avr/io.h>
+
+#if ARDUINO < 100 
+#include <WProgram.h> 
+#else 
+#include <Arduino.h> 
+#endif
+
+
+
+static uint8_t u8g_usart_spi_out(uint8_t data)
+{
+  /* send data */
+  UDR1 = data;
+  /* wait for empty transmit buffer */
+  while(!(UCSR1A & (1 << UDRE1)));
+
+  return  UDR1;
+}
+
+
+uint8_t u8g_com_arduino_hw_usart_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr)
+{
+  switch(msg)
+  {
+    case U8G_COM_MSG_STOP:
+      break;
+    
+    case U8G_COM_MSG_INIT:
+      /* SCK is already an output as we overwrite TXLED */
+      u8g_com_arduino_assign_pin_output_high(u8g);
+	  u8g_com_arduino_digital_write(u8g, U8G_PI_CS, HIGH);
+    
+	  // Init interface at 2MHz
+	  UBRR1 = 0x00;
+	  UCSR1C = (1 << UMSEL11) | (1 << UMSEL10);
+      UCSR1B = (1 << TXEN1);
+      UBRR1 = 3;
+           
+      break;
+    
+    case U8G_COM_MSG_ADDRESS:                     /* define cmd (arg_val = 0) or data mode (arg_val = 1) */
+      u8g_com_arduino_digital_write(u8g, U8G_PI_A0, arg_val);
+      break;
+
+    case U8G_COM_MSG_CHIP_SELECT:
+      if ( arg_val == 0 )
+      {
+        /* disable */
+        u8g_com_arduino_digital_write(u8g, U8G_PI_CS, HIGH);
+      }
+      else
+      {
+        /* enable */
+        u8g_com_arduino_digital_write(u8g, U8G_PI_CS, LOW);
+      }
+      break;
+      
+    case U8G_COM_MSG_RESET:
+      if ( u8g->pin_list[U8G_PI_RESET] != U8G_PIN_NONE )
+        u8g_com_arduino_digital_write(u8g, U8G_PI_RESET, arg_val);
+      break;
+    
+    case U8G_COM_MSG_WRITE_BYTE:
+      u8g_usart_spi_out(arg_val);
+      break;
+    
+    case U8G_COM_MSG_WRITE_SEQ:
+      {
+        register uint8_t *ptr = arg_ptr;
+        while( arg_val > 0 )
+        {
+          u8g_usart_spi_out(*ptr++);
+          arg_val--;
+        }
+      }
+      break;
+    case U8G_COM_MSG_WRITE_SEQ_P:
+      {
+        register uint8_t *ptr = arg_ptr;
+        while( arg_val > 0 )
+        {
+          u8g_usart_spi_out(u8g_pgm_read(ptr));
+          ptr++;
+          arg_val--;
+        }
+      }
+      break;
+  }
+  return 1;
+}
+
+/* #elif defined(__18CXX) || defined(__PIC32MX) */
+/* #elif defined(__arm__)		// Arduino Due, maybe we should better check for __SAM3X8E__ */
+
+#else /* __AVR_ATmega32U4__ */
+
+#endif /* __AVR_ATmega32U4__ */
+
+#else /* ARDUINO */
+
+uint8_t u8g_com_arduino_hw_usart_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr)
+{
+  return 1;
+}
+
+#endif /* ARDUINO */
+
+