24 lines
496 B
C
24 lines
496 B
C
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#include "spi.h"
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#include <avr/io.h>
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uint8_t spi_init(uint8_t spcr) {
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PORTB |= (1 << 5); // set SCK hi
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DDRB |= (1 << 5); // set SCK as output
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DDRB &= ~(1 << 4); // set MISO as input
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DDRB |= (1 << 3); // set MOSI as output
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DDRB |= (1 << 2); // SS must be output for Master mode to work
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SPCR = spcr | SPE;
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return(SPSR);
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}
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uint8_t spi_transfer(uint8_t in) {
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uint8_t v;
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SPDR = in;
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// wait for transfer to complete
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while(! (SPSR & (1<<SPIF)) ) {};
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v = SPDR;
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return(v);
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}
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