Remove STM32 variant (and submodule libopencm3)

[z180-stamp.git] / include / spi.h

/*
 * (C) Copyright 2009,2014 Leo C. <erbl259-lmu@yahoo.de>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#ifndef SPI_H_
#define SPI_H_

#define SPI_PORT      	PORTB		/* SPI Connection port */
#define SPI_DDR       	DDRB		/* SPI Direction port */
#define SPI_SS		0
#define SPI_SCK		1
#define SPI_MOSI	2
#define SPI_MISO	3


/* SPI macros */

#define SPI_SET_SPEED_F_2		do {SPCR = (1<<SPE) | (1<<MSTR) | (0<<SPR1) | (0<<SPR0); SPSR = (1<<SPI2X); } while(0)
#define SPI_SET_SPEED_F_4		do {SPCR = (1<<SPE) | (1<<MSTR) | (0<<SPR1) | (0<<SPR0); SPSR = (0<<SPI2X); } while(0)
#define SPI_SET_SPEED_F_8		do {SPCR = (1<<SPE) | (1<<MSTR) | (0<<SPR1) | (1<<SPR0); SPSR = (1<<SPI2X); } while(0)
#define SPI_SET_SPEED_F_16		do {SPCR = (1<<SPE) | (1<<MSTR) | (0<<SPR1) | (1<<SPR0); SPSR = (0<<SPI2X); } while(0)
#define SPI_SET_SPEED_F_32		do {SPCR = (1<<SPE) | (1<<MSTR) | (1<<SPR1) | (0<<SPR0); SPSR = (1<<SPI2X); } while(0)
#define SPI_SET_SPEED_F_64		do {SPCR = (1<<SPE) | (1<<MSTR) | (1<<SPR1) | (0<<SPR0); SPSR = (0<<SPI2X); } while(0)
#define SPI_SET_SPEED_F_128		do {SPCR = (1<<SPE) | (1<<MSTR) | (1<<SPR1) | (1<<SPR0); SPSR = (0<<SPI2X); } while(0)

/** switch to fast SPI Clock */
#define SPISetFastClock() 	 	SPI_SET_SPEED_F_2
#define SPISetSlowClock() 	 	SPI_SET_SPEED_F_8
#define SPISetMMCInitClock() 	SPI_SET_SPEED_F_64

#define SPI_OFF()				do { SPCR = 0; } while(0)

static inline __attribute__((always_inline)) void spi_wait() {
	loop_until_bit_is_set(SPSR,SPIF);
}

static inline __attribute__((always_inline)) void spi_write(uint8_t a) {
	SPDR = a;
}

static inline void spi_xmit(uint8_t a){
	spi_write(a);
	spi_wait();
}

static inline uint8_t spi_rcvr(void) {
	SPDR = 0xFF;
	spi_wait();
	return SPDR;
}

#endif /* SPI_H_ */