0,0 → 1,103 |
/**************************************************************************** |
* Copyright (C) 2009-2010 by Claas Anders "CaScAdE" Rathje * |
* admiralcascade@gmail.com * |
* Project-URL: http://www.mylifesucks.de/oss/c-osd/ * |
* * |
* This program is free software; you can redistribute it and/or modify * |
* it under the terms of the GNU General Public License as published by * |
* the Free Software Foundation; either version 2 of the License. * |
* * |
* This program 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 General Public License for more details. * |
* * |
* You should have received a copy of the GNU General Public License * |
* along with this program; if not, write to the * |
* Free Software Foundation, Inc., * |
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * |
****************************************************************************/ |
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#include <avr/io.h> |
#include <avr/interrupt.h> |
#include "spi.h" |
#include "main.h" |
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#if !(ALLCHARSDEBUG|(WRITECHARS != -1)) |
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volatile uint16_t icnt = 0; |
volatile uint8_t request_count = 0; |
volatile uint8_t spi_ready = 1; |
volatile union SPI_buffer_t SPI_buffer; |
int16_t ampere = 0, max_ampere = 0, s_volt; |
int32_t ampere_wasted = 0; |
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#define INT0_HIGH PORTD |= (1 << PD2); |
#define INT0_LOW PORTD &= ~(1 << PD2); |
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/** |
* init the SPI as master |
*/ |
void SpiMasterInit(void) { |
volatile char IOReg; |
// set PB4(/SS), PB5(MOSI), PB7(SCK) as output |
DDRB = (1 << PB4) | (1 << PB5) | (1 << PB7); |
PORTB |= (1 << PB4); // pullup SS |
// enable SPI Interrupt and SPI in Master Mode with SCK = CK/128 |
SPCR = (1 << SPIE) | (1 << SPE) | (1 << MSTR) | (1 << SPR0) | (1 << SPR1); |
IOReg = SPSR; // clear SPIF bit in SPSR |
IOReg = SPDR; |
//sei(); // we do it later |
} |
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/** |
* SPI interrupt handler |
*/ |
ISR(SPI_STC_vect) { |
if (request_count == 0) { |
SPI_buffer.buffer.chk = SPDR; // firs char received is check byte from last transfer |
} else { |
SPI_buffer.buffer.c[request_count - 1] = SPDR; // safe received byte to buffer |
} |
request_count++; |
if (--icnt) { |
//SPDR = *iptr; // send next byte |
spi_ready = 1; // we _should_ send later because the slave needs more time |
} else { |
SPCR &= ~_BV(SPIE); // deactivate interrupt |
INT0_HIGH // transfer is done, slave does not need to listen |
} |
} |
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/** |
* check if SPI transfer is still busy |
*/ |
int TransferIsBusy(void) { |
return SPCR & _BV(SPIE); |
} |
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/** |
* start a new transfer with length <len> |
*/ |
void StartTransfer(uint16_t len) { |
INT0_LOW // /SS LOW ^= SS HIGH ^= slave should listen |
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// this is a new request |
request_count = 0; |
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// set up pointer and length for interrupt handler |
icnt = len; |
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SPCR |= _BV(SPIE); // enable spi interrupt |
SPDR = 'A'; // start transfer by first command char |
} |
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/** |
* send next command through spi |
*/ |
void spi_send_next() { |
SPDR = 'A' + request_count; |
} |
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#endif |