ardupilot/libraries/SPI3/SPI3.h

71 lines
1.8 KiB
C++

/*
* SPI3.cpp - SPI library using UART3 for Ardupilot Mega
* Code by Randy Mackay. DIYDrones.com
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
*/
#ifndef _SPI3_H_INCLUDED
#define _SPI3_H_INCLUDED
#include <stdio.h>
#include <Arduino.h>
#include <avr/pgmspace.h>
// SPI3's standard pins on Atmega2560
#define SPI3_SCK PJ2
#define SPI3_MOSI 14
#define SPI3_MISO 15
// used to change UART into SPI mode
#define SPI3_USART_MASK 0xC0 // UMSEL31 | UMSEL30
#define SPI3_USART_ASYNC_UART 0x00 // UMSEL31 = 0, UMSEL30 = 0
#define SPI3_USART_SYNC_UART 0x40 // UMSEL31 = 0, UMSEL30 = 1
#define SPI3_USART_SPI_MASTER 0xC0 // UMSEL31 = 1, UMSEL30 = 1
// spi bus speeds. these assume a 16Mhz clock
#define SPI3_SPEED_8MHZ 0x00
#define SPI3_SPEED_2MHZ 0x04
// default speed
#define SPI3_DEFAULT_SPEED SPI3_SPEED_2MHZ // 2 megahertz
// SPI mode definitions
#define SPI3_MODE_MASK 0x03
#define SPI3_MODE0 0x00
#define SPI3_MODE1 0x01
#define SPI3_MODE2 0x02
#define SPI3_MODE3 0x03
#define SPI3_DEFAULT_MODE SPI3_MODE0
#define SPI3_CLOCK_MASK 0x03 // SPR1 = bit 1, SPR0 = bit 0 on SPCR
#define SPI3_2XCLOCK_MASK 0x01 // SPI2X = bit 0 on SPSR
// SPI bit order
#define SPI3_MSBFIRST 0x00
#define SPI3_LSBFIRST 0x01
class SPI3Class {
public:
static void begin();
static void end();
static uint8_t transfer(byte data);
// SPI Configuration methods
static void setBitOrder(uint8_t bitOrder);
static void setDataMode(uint8_t mode);
static void setSpeed(uint8_t rate);
private:
static bool _initialised;
};
extern SPI3Class SPI3;
#endif