27 lines
521 B
C
27 lines
521 B
C
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/*
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* spi.c
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*
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* Copyright 2011 Mika Tuupola
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*
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* Licensed under the MIT license:
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* http://www.opensource.org/licenses/mit-license.php
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*
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*/
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#include "digital.h"
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#include "spi.h"
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void spi_init(void) {
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pin_mode(SPI_SCK, OUTPUT);
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pin_mode(SPI_MOSI, OUTPUT);
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pin_mode(SPI_SS, OUTPUT); /* Must be output in Master mode. */
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spi_set_msb();
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spi_set_master();
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spi_enable();
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}
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uint8_t spi_transfer(volatile uint8_t data) {
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SPDR = data;
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loop_until_bit_is_set(SPSR, SPIF);
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return SPDR;
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}
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