add spi and eeprom arduino libs
This commit is contained in:
parent
cfca07489d
commit
dfea93b2ff
146
cpu/avr/dev/arduino/EEPROM.h
Normal file
146
cpu/avr/dev/arduino/EEPROM.h
Normal file
|
@ -0,0 +1,146 @@
|
|||
/*
|
||||
EEPROM.h - EEPROM library
|
||||
Original Copyright (c) 2006 David A. Mellis. All right reserved.
|
||||
New version by Christopher Andrews 2015.
|
||||
|
||||
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.
|
||||
|
||||
This library is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public
|
||||
License along with this library; if not, write to the Free Software
|
||||
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
*/
|
||||
|
||||
#ifndef EEPROM_h
|
||||
#define EEPROM_h
|
||||
|
||||
#include <inttypes.h>
|
||||
#include <avr/eeprom.h>
|
||||
#include <avr/io.h>
|
||||
|
||||
/***
|
||||
EERef class.
|
||||
|
||||
This object references an EEPROM cell.
|
||||
Its purpose is to mimic a typical byte of RAM, however its storage is the EEPROM.
|
||||
This class has an overhead of two bytes, similar to storing a pointer to an EEPROM cell.
|
||||
***/
|
||||
|
||||
struct EERef{
|
||||
|
||||
EERef( const int index )
|
||||
: index( index ) {}
|
||||
|
||||
//Access/read members.
|
||||
uint8_t operator*() const { return eeprom_read_byte( (uint8_t*) index ); }
|
||||
operator const uint8_t() const { return **this; }
|
||||
|
||||
//Assignment/write members.
|
||||
EERef &operator=( const EERef &ref ) { return *this = *ref; }
|
||||
EERef &operator=( uint8_t in ) { return eeprom_write_byte( (uint8_t*) index, in ), *this; }
|
||||
EERef &operator +=( uint8_t in ) { return *this = **this + in; }
|
||||
EERef &operator -=( uint8_t in ) { return *this = **this - in; }
|
||||
EERef &operator *=( uint8_t in ) { return *this = **this * in; }
|
||||
EERef &operator /=( uint8_t in ) { return *this = **this / in; }
|
||||
EERef &operator ^=( uint8_t in ) { return *this = **this ^ in; }
|
||||
EERef &operator %=( uint8_t in ) { return *this = **this % in; }
|
||||
EERef &operator &=( uint8_t in ) { return *this = **this & in; }
|
||||
EERef &operator |=( uint8_t in ) { return *this = **this | in; }
|
||||
EERef &operator <<=( uint8_t in ) { return *this = **this << in; }
|
||||
EERef &operator >>=( uint8_t in ) { return *this = **this >> in; }
|
||||
|
||||
EERef &update( uint8_t in ) { return in != *this ? *this = in : *this; }
|
||||
|
||||
/** Prefix increment/decrement **/
|
||||
EERef& operator++() { return *this += 1; }
|
||||
EERef& operator--() { return *this -= 1; }
|
||||
|
||||
/** Postfix increment/decrement **/
|
||||
uint8_t operator++ (int){
|
||||
uint8_t ret = **this;
|
||||
return ++(*this), ret;
|
||||
}
|
||||
|
||||
uint8_t operator-- (int){
|
||||
uint8_t ret = **this;
|
||||
return --(*this), ret;
|
||||
}
|
||||
|
||||
int index; //Index of current EEPROM cell.
|
||||
};
|
||||
|
||||
/***
|
||||
EEPtr class.
|
||||
|
||||
This object is a bidirectional pointer to EEPROM cells represented by EERef objects.
|
||||
Just like a normal pointer type, this can be dereferenced and repositioned using
|
||||
increment/decrement operators.
|
||||
***/
|
||||
|
||||
struct EEPtr{
|
||||
|
||||
EEPtr( const int index )
|
||||
: index( index ) {}
|
||||
|
||||
operator const int() const { return index; }
|
||||
EEPtr &operator=( int in ) { return index = in, *this; }
|
||||
|
||||
//Iterator functionality.
|
||||
bool operator!=( const EEPtr &ptr ) { return index != ptr.index; }
|
||||
EERef operator*() { return index; }
|
||||
|
||||
/** Prefix & Postfix increment/decrement **/
|
||||
EEPtr& operator++() { return ++index, *this; }
|
||||
EEPtr& operator--() { return --index, *this; }
|
||||
EEPtr operator++ (int) { return index++; }
|
||||
EEPtr operator-- (int) { return index--; }
|
||||
|
||||
int index; //Index of current EEPROM cell.
|
||||
};
|
||||
|
||||
/***
|
||||
EEPROMClass class.
|
||||
|
||||
This object represents the entire EEPROM space.
|
||||
It wraps the functionality of EEPtr and EERef into a basic interface.
|
||||
This class is also 100% backwards compatible with earlier Arduino core releases.
|
||||
***/
|
||||
|
||||
struct EEPROMClass{
|
||||
|
||||
//Basic user access methods.
|
||||
EERef operator[]( const int idx ) { return idx; }
|
||||
uint8_t read( int idx ) { return EERef( idx ); }
|
||||
void write( int idx, uint8_t val ) { (EERef( idx )) = val; }
|
||||
void update( int idx, uint8_t val ) { EERef( idx ).update( val ); }
|
||||
|
||||
//STL and C++11 iteration capability.
|
||||
EEPtr begin() { return 0x00; }
|
||||
EEPtr end() { return length(); } //Standards requires this to be the item after the last valid entry. The returned pointer is invalid.
|
||||
uint16_t length() { return E2END + 1; }
|
||||
|
||||
//Functionality to 'get' and 'put' objects to and from EEPROM.
|
||||
template< typename T > T &get( int idx, T &t ){
|
||||
EEPtr e = idx;
|
||||
uint8_t *ptr = (uint8_t*) &t;
|
||||
for( int count = sizeof(T) ; count ; --count, ++e ) *ptr++ = *e;
|
||||
return t;
|
||||
}
|
||||
|
||||
template< typename T > const T &put( int idx, const T &t ){
|
||||
EEPtr e = idx;
|
||||
const uint8_t *ptr = (const uint8_t*) &t;
|
||||
for( int count = sizeof(T) ; count ; --count, ++e ) (*e).update( *ptr++ );
|
||||
return t;
|
||||
}
|
||||
};
|
||||
|
||||
static EEPROMClass EEPROM;
|
||||
#endif
|
201
cpu/avr/dev/arduino/SPI.cpp
Normal file
201
cpu/avr/dev/arduino/SPI.cpp
Normal file
|
@ -0,0 +1,201 @@
|
|||
/*
|
||||
* Copyright (c) 2010 by Cristian Maglie <c.maglie@arduino.cc>
|
||||
* Copyright (c) 2014 by Paul Stoffregen <paul@pjrc.com> (Transaction API)
|
||||
* Copyright (c) 2014 by Matthijs Kooijman <matthijs@stdin.nl> (SPISettings AVR)
|
||||
* Copyright (c) 2014 by Andrew J. Kroll <xxxajk@gmail.com> (atomicity fixes)
|
||||
* SPI Master library for arduino.
|
||||
*
|
||||
* This file is free software; you can redistribute it and/or modify
|
||||
* it under the terms of either the GNU General Public License version 2
|
||||
* or the GNU Lesser General Public License version 2.1, both as
|
||||
* published by the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include "SPI.h"
|
||||
|
||||
SPIClass SPI;
|
||||
|
||||
uint8_t SPIClass::initialized = 0;
|
||||
uint8_t SPIClass::interruptMode = 0;
|
||||
uint8_t SPIClass::interruptMask = 0;
|
||||
uint8_t SPIClass::interruptSave = 0;
|
||||
#ifdef SPI_TRANSACTION_MISMATCH_LED
|
||||
uint8_t SPIClass::inTransactionFlag = 0;
|
||||
#endif
|
||||
|
||||
void SPIClass::begin()
|
||||
{
|
||||
uint8_t sreg = SREG;
|
||||
noInterrupts(); // Protect from a scheduler and prevent transactionBegin
|
||||
if (!initialized) {
|
||||
// Set SS to high so a connected chip will be "deselected" by default
|
||||
uint8_t port = digitalPinToPort(SS);
|
||||
uint8_t bit = digitalPinToBitMask(SS);
|
||||
volatile uint8_t *reg = portModeRegister(port);
|
||||
|
||||
// if the SS pin is not already configured as an output
|
||||
// then set it high (to enable the internal pull-up resistor)
|
||||
if(!(*reg & bit)){
|
||||
digitalWrite(SS, HIGH);
|
||||
}
|
||||
|
||||
// When the SS pin is set as OUTPUT, it can be used as
|
||||
// a general purpose output port (it doesn't influence
|
||||
// SPI operations).
|
||||
pinMode(SS, OUTPUT);
|
||||
|
||||
// Warning: if the SS pin ever becomes a LOW INPUT then SPI
|
||||
// automatically switches to Slave, so the data direction of
|
||||
// the SS pin MUST be kept as OUTPUT.
|
||||
SPCR |= _BV(MSTR);
|
||||
SPCR |= _BV(SPE);
|
||||
|
||||
// Set direction register for SCK and MOSI pin.
|
||||
// MISO pin automatically overrides to INPUT.
|
||||
// By doing this AFTER enabling SPI, we avoid accidentally
|
||||
// clocking in a single bit since the lines go directly
|
||||
// from "input" to SPI control.
|
||||
// http://code.google.com/p/arduino/issues/detail?id=888
|
||||
pinMode(SCK, OUTPUT);
|
||||
pinMode(MOSI, OUTPUT);
|
||||
}
|
||||
initialized++; // reference count
|
||||
SREG = sreg;
|
||||
}
|
||||
|
||||
void SPIClass::end() {
|
||||
uint8_t sreg = SREG;
|
||||
noInterrupts(); // Protect from a scheduler and prevent transactionBegin
|
||||
// Decrease the reference counter
|
||||
if (initialized)
|
||||
initialized--;
|
||||
// If there are no more references disable SPI
|
||||
if (!initialized) {
|
||||
SPCR &= ~_BV(SPE);
|
||||
interruptMode = 0;
|
||||
#ifdef SPI_TRANSACTION_MISMATCH_LED
|
||||
inTransactionFlag = 0;
|
||||
#endif
|
||||
}
|
||||
SREG = sreg;
|
||||
}
|
||||
|
||||
// mapping of interrupt numbers to bits within SPI_AVR_EIMSK
|
||||
#if defined(__AVR_ATmega32U4__)
|
||||
#define SPI_INT0_MASK (1<<INT0)
|
||||
#define SPI_INT1_MASK (1<<INT1)
|
||||
#define SPI_INT2_MASK (1<<INT2)
|
||||
#define SPI_INT3_MASK (1<<INT3)
|
||||
#define SPI_INT4_MASK (1<<INT6)
|
||||
#elif defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB1286__)
|
||||
#define SPI_INT0_MASK (1<<INT0)
|
||||
#define SPI_INT1_MASK (1<<INT1)
|
||||
#define SPI_INT2_MASK (1<<INT2)
|
||||
#define SPI_INT3_MASK (1<<INT3)
|
||||
#define SPI_INT4_MASK (1<<INT4)
|
||||
#define SPI_INT5_MASK (1<<INT5)
|
||||
#define SPI_INT6_MASK (1<<INT6)
|
||||
#define SPI_INT7_MASK (1<<INT7)
|
||||
#elif defined(EICRA) && defined(EICRB) && defined(EIMSK)
|
||||
#define SPI_INT0_MASK (1<<INT4)
|
||||
#define SPI_INT1_MASK (1<<INT5)
|
||||
#define SPI_INT2_MASK (1<<INT0)
|
||||
#define SPI_INT3_MASK (1<<INT1)
|
||||
#define SPI_INT4_MASK (1<<INT2)
|
||||
#define SPI_INT5_MASK (1<<INT3)
|
||||
#define SPI_INT6_MASK (1<<INT6)
|
||||
#define SPI_INT7_MASK (1<<INT7)
|
||||
#else
|
||||
#ifdef INT0
|
||||
#define SPI_INT0_MASK (1<<INT0)
|
||||
#endif
|
||||
#ifdef INT1
|
||||
#define SPI_INT1_MASK (1<<INT1)
|
||||
#endif
|
||||
#ifdef INT2
|
||||
#define SPI_INT2_MASK (1<<INT2)
|
||||
#endif
|
||||
#endif
|
||||
|
||||
void SPIClass::usingInterrupt(uint8_t interruptNumber)
|
||||
{
|
||||
uint8_t mask = 0;
|
||||
uint8_t sreg = SREG;
|
||||
noInterrupts(); // Protect from a scheduler and prevent transactionBegin
|
||||
switch (interruptNumber) {
|
||||
#ifdef SPI_INT0_MASK
|
||||
case 0: mask = SPI_INT0_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT1_MASK
|
||||
case 1: mask = SPI_INT1_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT2_MASK
|
||||
case 2: mask = SPI_INT2_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT3_MASK
|
||||
case 3: mask = SPI_INT3_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT4_MASK
|
||||
case 4: mask = SPI_INT4_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT5_MASK
|
||||
case 5: mask = SPI_INT5_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT6_MASK
|
||||
case 6: mask = SPI_INT6_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT7_MASK
|
||||
case 7: mask = SPI_INT7_MASK; break;
|
||||
#endif
|
||||
default:
|
||||
interruptMode = 2;
|
||||
break;
|
||||
}
|
||||
interruptMask |= mask;
|
||||
if (!interruptMode)
|
||||
interruptMode = 1;
|
||||
SREG = sreg;
|
||||
}
|
||||
|
||||
void SPIClass::notUsingInterrupt(uint8_t interruptNumber)
|
||||
{
|
||||
// Once in mode 2 we can't go back to 0 without a proper reference count
|
||||
if (interruptMode == 2)
|
||||
return;
|
||||
uint8_t mask = 0;
|
||||
uint8_t sreg = SREG;
|
||||
noInterrupts(); // Protect from a scheduler and prevent transactionBegin
|
||||
switch (interruptNumber) {
|
||||
#ifdef SPI_INT0_MASK
|
||||
case 0: mask = SPI_INT0_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT1_MASK
|
||||
case 1: mask = SPI_INT1_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT2_MASK
|
||||
case 2: mask = SPI_INT2_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT3_MASK
|
||||
case 3: mask = SPI_INT3_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT4_MASK
|
||||
case 4: mask = SPI_INT4_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT5_MASK
|
||||
case 5: mask = SPI_INT5_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT6_MASK
|
||||
case 6: mask = SPI_INT6_MASK; break;
|
||||
#endif
|
||||
#ifdef SPI_INT7_MASK
|
||||
case 7: mask = SPI_INT7_MASK; break;
|
||||
#endif
|
||||
default:
|
||||
break;
|
||||
// this case can't be reached
|
||||
}
|
||||
interruptMask &= ~mask;
|
||||
if (!interruptMask)
|
||||
interruptMode = 0;
|
||||
SREG = sreg;
|
||||
}
|
324
cpu/avr/dev/arduino/SPI.h
Normal file
324
cpu/avr/dev/arduino/SPI.h
Normal file
|
@ -0,0 +1,324 @@
|
|||
/*
|
||||
* Copyright (c) 2010 by Cristian Maglie <c.maglie@arduino.cc>
|
||||
* Copyright (c) 2014 by Paul Stoffregen <paul@pjrc.com> (Transaction API)
|
||||
* Copyright (c) 2014 by Matthijs Kooijman <matthijs@stdin.nl> (SPISettings AVR)
|
||||
* Copyright (c) 2014 by Andrew J. Kroll <xxxajk@gmail.com> (atomicity fixes)
|
||||
* SPI Master library for arduino.
|
||||
*
|
||||
* This file is free software; you can redistribute it and/or modify
|
||||
* it under the terms of either the GNU General Public License version 2
|
||||
* or the GNU Lesser General Public License version 2.1, both as
|
||||
* published by the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#ifndef _SPI_H_INCLUDED
|
||||
#define _SPI_H_INCLUDED
|
||||
|
||||
#include <Arduino.h>
|
||||
|
||||
// SPI_HAS_TRANSACTION means SPI has beginTransaction(), endTransaction(),
|
||||
// usingInterrupt(), and SPISetting(clock, bitOrder, dataMode)
|
||||
#define SPI_HAS_TRANSACTION 1
|
||||
|
||||
// SPI_HAS_NOTUSINGINTERRUPT means that SPI has notUsingInterrupt() method
|
||||
#define SPI_HAS_NOTUSINGINTERRUPT 1
|
||||
|
||||
// SPI_ATOMIC_VERSION means that SPI has atomicity fixes and what version.
|
||||
// This way when there is a bug fix you can check this define to alert users
|
||||
// of your code if it uses better version of this library.
|
||||
// This also implies everything that SPI_HAS_TRANSACTION as documented above is
|
||||
// available too.
|
||||
#define SPI_ATOMIC_VERSION 1
|
||||
|
||||
// Uncomment this line to add detection of mismatched begin/end transactions.
|
||||
// A mismatch occurs if other libraries fail to use SPI.endTransaction() for
|
||||
// each SPI.beginTransaction(). Connect an LED to this pin. The LED will turn
|
||||
// on if any mismatch is ever detected.
|
||||
//#define SPI_TRANSACTION_MISMATCH_LED 5
|
||||
|
||||
#ifndef LSBFIRST
|
||||
#define LSBFIRST 0
|
||||
#endif
|
||||
#ifndef MSBFIRST
|
||||
#define MSBFIRST 1
|
||||
#endif
|
||||
|
||||
#define SPI_CLOCK_DIV4 0x00
|
||||
#define SPI_CLOCK_DIV16 0x01
|
||||
#define SPI_CLOCK_DIV64 0x02
|
||||
#define SPI_CLOCK_DIV128 0x03
|
||||
#define SPI_CLOCK_DIV2 0x04
|
||||
#define SPI_CLOCK_DIV8 0x05
|
||||
#define SPI_CLOCK_DIV32 0x06
|
||||
|
||||
#define SPI_MODE0 0x00
|
||||
#define SPI_MODE1 0x04
|
||||
#define SPI_MODE2 0x08
|
||||
#define SPI_MODE3 0x0C
|
||||
|
||||
#define SPI_MODE_MASK 0x0C // CPOL = bit 3, CPHA = bit 2 on SPCR
|
||||
#define SPI_CLOCK_MASK 0x03 // SPR1 = bit 1, SPR0 = bit 0 on SPCR
|
||||
#define SPI_2XCLOCK_MASK 0x01 // SPI2X = bit 0 on SPSR
|
||||
|
||||
// define SPI_AVR_EIMSK for AVR boards with external interrupt pins
|
||||
#if defined(EIMSK)
|
||||
#define SPI_AVR_EIMSK EIMSK
|
||||
#elif defined(GICR)
|
||||
#define SPI_AVR_EIMSK GICR
|
||||
#elif defined(GIMSK)
|
||||
#define SPI_AVR_EIMSK GIMSK
|
||||
#endif
|
||||
|
||||
class SPISettings {
|
||||
public:
|
||||
SPISettings(uint32_t clock, uint8_t bitOrder, uint8_t dataMode) {
|
||||
if (__builtin_constant_p(clock)) {
|
||||
init_AlwaysInline(clock, bitOrder, dataMode);
|
||||
} else {
|
||||
init_MightInline(clock, bitOrder, dataMode);
|
||||
}
|
||||
}
|
||||
SPISettings() {
|
||||
init_AlwaysInline(4000000, MSBFIRST, SPI_MODE0);
|
||||
}
|
||||
private:
|
||||
void init_MightInline(uint32_t clock, uint8_t bitOrder, uint8_t dataMode) {
|
||||
init_AlwaysInline(clock, bitOrder, dataMode);
|
||||
}
|
||||
void init_AlwaysInline(uint32_t clock, uint8_t bitOrder, uint8_t dataMode)
|
||||
__attribute__((__always_inline__)) {
|
||||
// Clock settings are defined as follows. Note that this shows SPI2X
|
||||
// inverted, so the bits form increasing numbers. Also note that
|
||||
// fosc/64 appears twice
|
||||
// SPR1 SPR0 ~SPI2X Freq
|
||||
// 0 0 0 fosc/2
|
||||
// 0 0 1 fosc/4
|
||||
// 0 1 0 fosc/8
|
||||
// 0 1 1 fosc/16
|
||||
// 1 0 0 fosc/32
|
||||
// 1 0 1 fosc/64
|
||||
// 1 1 0 fosc/64
|
||||
// 1 1 1 fosc/128
|
||||
|
||||
// We find the fastest clock that is less than or equal to the
|
||||
// given clock rate. The clock divider that results in clock_setting
|
||||
// is 2 ^^ (clock_div + 1). If nothing is slow enough, we'll use the
|
||||
// slowest (128 == 2 ^^ 7, so clock_div = 6).
|
||||
uint8_t clockDiv;
|
||||
|
||||
// When the clock is known at compiletime, use this if-then-else
|
||||
// cascade, which the compiler knows how to completely optimize
|
||||
// away. When clock is not known, use a loop instead, which generates
|
||||
// shorter code.
|
||||
if (__builtin_constant_p(clock)) {
|
||||
if (clock >= F_CPU / 2) {
|
||||
clockDiv = 0;
|
||||
} else if (clock >= F_CPU / 4) {
|
||||
clockDiv = 1;
|
||||
} else if (clock >= F_CPU / 8) {
|
||||
clockDiv = 2;
|
||||
} else if (clock >= F_CPU / 16) {
|
||||
clockDiv = 3;
|
||||
} else if (clock >= F_CPU / 32) {
|
||||
clockDiv = 4;
|
||||
} else if (clock >= F_CPU / 64) {
|
||||
clockDiv = 5;
|
||||
} else {
|
||||
clockDiv = 6;
|
||||
}
|
||||
} else {
|
||||
uint32_t clockSetting = F_CPU / 2;
|
||||
clockDiv = 0;
|
||||
while (clockDiv < 6 && clock < clockSetting) {
|
||||
clockSetting /= 2;
|
||||
clockDiv++;
|
||||
}
|
||||
}
|
||||
|
||||
// Compensate for the duplicate fosc/64
|
||||
if (clockDiv == 6)
|
||||
clockDiv = 7;
|
||||
|
||||
// Invert the SPI2X bit
|
||||
clockDiv ^= 0x1;
|
||||
|
||||
// Pack into the SPISettings class
|
||||
spcr = _BV(SPE) | _BV(MSTR) | ((bitOrder == LSBFIRST) ? _BV(DORD) : 0) |
|
||||
(dataMode & SPI_MODE_MASK) | ((clockDiv >> 1) & SPI_CLOCK_MASK);
|
||||
spsr = clockDiv & SPI_2XCLOCK_MASK;
|
||||
}
|
||||
uint8_t spcr;
|
||||
uint8_t spsr;
|
||||
friend class SPIClass;
|
||||
};
|
||||
|
||||
|
||||
class SPIClass {
|
||||
public:
|
||||
// Initialize the SPI library
|
||||
static void begin();
|
||||
|
||||
// If SPI is used from within an interrupt, this function registers
|
||||
// that interrupt with the SPI library, so beginTransaction() can
|
||||
// prevent conflicts. The input interruptNumber is the number used
|
||||
// with attachInterrupt. If SPI is used from a different interrupt
|
||||
// (eg, a timer), interruptNumber should be 255.
|
||||
static void usingInterrupt(uint8_t interruptNumber);
|
||||
// And this does the opposite.
|
||||
static void notUsingInterrupt(uint8_t interruptNumber);
|
||||
// Note: the usingInterrupt and notUsingInterrupt functions should
|
||||
// not to be called from ISR context or inside a transaction.
|
||||
// For details see:
|
||||
// https://github.com/arduino/Arduino/pull/2381
|
||||
// https://github.com/arduino/Arduino/pull/2449
|
||||
|
||||
// Before using SPI.transfer() or asserting chip select pins,
|
||||
// this function is used to gain exclusive access to the SPI bus
|
||||
// and configure the correct settings.
|
||||
inline static void beginTransaction(SPISettings settings) {
|
||||
if (interruptMode > 0) {
|
||||
uint8_t sreg = SREG;
|
||||
noInterrupts();
|
||||
|
||||
#ifdef SPI_AVR_EIMSK
|
||||
if (interruptMode == 1) {
|
||||
interruptSave = SPI_AVR_EIMSK;
|
||||
SPI_AVR_EIMSK &= ~interruptMask;
|
||||
SREG = sreg;
|
||||
} else
|
||||
#endif
|
||||
{
|
||||
interruptSave = sreg;
|
||||
}
|
||||
}
|
||||
|
||||
#ifdef SPI_TRANSACTION_MISMATCH_LED
|
||||
if (inTransactionFlag) {
|
||||
pinMode(SPI_TRANSACTION_MISMATCH_LED, OUTPUT);
|
||||
digitalWrite(SPI_TRANSACTION_MISMATCH_LED, HIGH);
|
||||
}
|
||||
inTransactionFlag = 1;
|
||||
#endif
|
||||
|
||||
SPCR = settings.spcr;
|
||||
SPSR = settings.spsr;
|
||||
}
|
||||
|
||||
// Write to the SPI bus (MOSI pin) and also receive (MISO pin)
|
||||
inline static uint8_t transfer(uint8_t data) {
|
||||
SPDR = data;
|
||||
/*
|
||||
* The following NOP introduces a small delay that can prevent the wait
|
||||
* loop form iterating when running at the maximum speed. This gives
|
||||
* about 10% more speed, even if it seems counter-intuitive. At lower
|
||||
* speeds it is unnoticed.
|
||||
*/
|
||||
asm volatile("nop");
|
||||
while (!(SPSR & _BV(SPIF))) ; // wait
|
||||
return SPDR;
|
||||
}
|
||||
inline static uint16_t transfer16(uint16_t data) {
|
||||
union { uint16_t val; struct { uint8_t lsb; uint8_t msb; }; } in, out;
|
||||
in.val = data;
|
||||
if (!(SPCR & _BV(DORD))) {
|
||||
SPDR = in.msb;
|
||||
asm volatile("nop"); // See transfer(uint8_t) function
|
||||
while (!(SPSR & _BV(SPIF))) ;
|
||||
out.msb = SPDR;
|
||||
SPDR = in.lsb;
|
||||
asm volatile("nop");
|
||||
while (!(SPSR & _BV(SPIF))) ;
|
||||
out.lsb = SPDR;
|
||||
} else {
|
||||
SPDR = in.lsb;
|
||||
asm volatile("nop");
|
||||
while (!(SPSR & _BV(SPIF))) ;
|
||||
out.lsb = SPDR;
|
||||
SPDR = in.msb;
|
||||
asm volatile("nop");
|
||||
while (!(SPSR & _BV(SPIF))) ;
|
||||
out.msb = SPDR;
|
||||
}
|
||||
return out.val;
|
||||
}
|
||||
inline static void transfer(void *buf, size_t count) {
|
||||
if (count == 0) return;
|
||||
uint8_t *p = (uint8_t *)buf;
|
||||
SPDR = *p;
|
||||
while (--count > 0) {
|
||||
uint8_t out = *(p + 1);
|
||||
while (!(SPSR & _BV(SPIF))) ;
|
||||
uint8_t in = SPDR;
|
||||
SPDR = out;
|
||||
*p++ = in;
|
||||
}
|
||||
while (!(SPSR & _BV(SPIF))) ;
|
||||
*p = SPDR;
|
||||
}
|
||||
// After performing a group of transfers and releasing the chip select
|
||||
// signal, this function allows others to access the SPI bus
|
||||
inline static void endTransaction(void) {
|
||||
#ifdef SPI_TRANSACTION_MISMATCH_LED
|
||||
if (!inTransactionFlag) {
|
||||
pinMode(SPI_TRANSACTION_MISMATCH_LED, OUTPUT);
|
||||
digitalWrite(SPI_TRANSACTION_MISMATCH_LED, HIGH);
|
||||
}
|
||||
inTransactionFlag = 0;
|
||||
#endif
|
||||
|
||||
if (interruptMode > 0) {
|
||||
#ifdef SPI_AVR_EIMSK
|
||||
uint8_t sreg = SREG;
|
||||
#endif
|
||||
noInterrupts();
|
||||
#ifdef SPI_AVR_EIMSK
|
||||
if (interruptMode == 1) {
|
||||
SPI_AVR_EIMSK = interruptSave;
|
||||
SREG = sreg;
|
||||
} else
|
||||
#endif
|
||||
{
|
||||
SREG = interruptSave;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Disable the SPI bus
|
||||
static void end();
|
||||
|
||||
// This function is deprecated. New applications should use
|
||||
// beginTransaction() to configure SPI settings.
|
||||
inline static void setBitOrder(uint8_t bitOrder) {
|
||||
if (bitOrder == LSBFIRST) SPCR |= _BV(DORD);
|
||||
else SPCR &= ~(_BV(DORD));
|
||||
}
|
||||
// This function is deprecated. New applications should use
|
||||
// beginTransaction() to configure SPI settings.
|
||||
inline static void setDataMode(uint8_t dataMode) {
|
||||
SPCR = (SPCR & ~SPI_MODE_MASK) | dataMode;
|
||||
}
|
||||
// This function is deprecated. New applications should use
|
||||
// beginTransaction() to configure SPI settings.
|
||||
inline static void setClockDivider(uint8_t clockDiv) {
|
||||
SPCR = (SPCR & ~SPI_CLOCK_MASK) | (clockDiv & SPI_CLOCK_MASK);
|
||||
SPSR = (SPSR & ~SPI_2XCLOCK_MASK) | ((clockDiv >> 2) & SPI_2XCLOCK_MASK);
|
||||
}
|
||||
// These undocumented functions should not be used. SPI.transfer()
|
||||
// polls the hardware flag which is automatically cleared as the
|
||||
// AVR responds to SPI's interrupt
|
||||
inline static void attachInterrupt() { SPCR |= _BV(SPIE); }
|
||||
inline static void detachInterrupt() { SPCR &= ~_BV(SPIE); }
|
||||
|
||||
private:
|
||||
static uint8_t initialized;
|
||||
static uint8_t interruptMode; // 0=none, 1=mask, 2=global
|
||||
static uint8_t interruptMask; // which interrupts to mask
|
||||
static uint8_t interruptSave; // temp storage, to restore state
|
||||
#ifdef SPI_TRANSACTION_MISMATCH_LED
|
||||
static uint8_t inTransactionFlag;
|
||||
#endif
|
||||
};
|
||||
|
||||
extern SPIClass SPI;
|
||||
|
||||
#endif
|
Loading…
Reference in a new issue