From bdd377580a0374cc2893d386eb0f47b802232ac9 Mon Sep 17 00:00:00 2001 From: Nicolas Schodet Date: Fri, 17 Apr 2009 00:25:16 +0200 Subject: * digital/avr/modules/spi: - fixed bad SPI2X mode. - prepare for software driver. --- digital/avr/modules/spi/spi_hard.avr.c | 109 +++++++++++++++++++++++++++++++++ 1 file changed, 109 insertions(+) create mode 100644 digital/avr/modules/spi/spi_hard.avr.c (limited to 'digital/avr/modules/spi/spi_hard.avr.c') diff --git a/digital/avr/modules/spi/spi_hard.avr.c b/digital/avr/modules/spi/spi_hard.avr.c new file mode 100644 index 00000000..15282dde --- /dev/null +++ b/digital/avr/modules/spi/spi_hard.avr.c @@ -0,0 +1,109 @@ +/* spi_hard.avr.c - SPI driver using hardware implementation. */ +/* avr.spi - SPI AVR module. {{{ + * + * Copyright (C) 2008 NĂ©lio Laranjeiro + * + * APBTeam: + * Web: http://apbteam.org/ + * Email: team AT apbteam DOT org + * + * 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, or + * (at your option) any later version. + * + * 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. + * + * }}} */ +#include "common.h" + +#include "io.h" + +#include "spi.h" + +#if SPI0_DRIVER == SPI_DRIVER_HARD || SPI1_DRIVER == SPI_DRIVER_HARD + +#if defined (__AVR_ATmega128__) \ + || defined (__AVR_ATmega64__) \ + || defined (__AVR_AT90USB162__) +# define SPI_SS_IO B, 0 +# define SPI_SCK_IO B, 1 +# define SPI_MOSI_IO B, 2 +# define SPI_MISO_IO B, 3 +#elif defined (__AVR_ATmega16__) +# define SPI_SS_IO B, 4 +# define SPI_SCK_IO B, 7 +# define SPI_MOSI_IO B, 5 +# define SPI_MISO_IO B, 6 +#else +# error "spi: not implemented on this chip" +#endif + +void +spi_hard_init_ (uint8_t spcr, uint8_t spi2x) +{ + if (spcr & SPI_MASTER) + { + /* Master configuration. */ + /* SS must be output or SPI could switch to slave mode. */ + IO_PORT (SPI_SS_IO) |= IO_BV (SPI_SS_IO); + IO_DDR (SPI_SS_IO) |= IO_BV (SPI_SS_IO); + IO_DDR (SPI_MISO_IO) &= ~IO_BV (SPI_MISO_IO); + IO_PORT (SPI_MISO_IO) &= ~IO_BV (SPI_MISO_IO); + IO_PORT (SPI_MOSI_IO) |= IO_BV (SPI_MOSI_IO); + IO_DDR (SPI_MOSI_IO) |= IO_BV (SPI_MOSI_IO); + IO_PORT (SPI_SCK_IO) |= IO_BV (SPI_SCK_IO); + IO_DDR (SPI_SCK_IO) |= IO_BV (SPI_SCK_IO); + } + else + { + /* Slave configuration, will set MISO later. */ + IO_DDR (SPI_SS_IO) &= ~IO_BV (SPI_SS_IO); + IO_PORT (SPI_SS_IO) |= IO_BV (SPI_SS_IO); + IO_DDR (SPI_MOSI_IO) &= ~IO_BV (SPI_MOSI_IO); + IO_PORT (SPI_MOSI_IO) &= ~IO_BV (SPI_MOSI_IO); + IO_DDR (SPI_SCK_IO) &= ~IO_BV (SPI_SCK_IO); + IO_PORT (SPI_SCK_IO) &= ~IO_BV (SPI_SCK_IO); + } + SPCR = spcr | _BV (SPE); + SPSR = spi2x; + if (!(spcr & SPI_MASTER)) + { + /* Slave configuration, set MISO now or else it will be an output for + * a short time until SPI is activate. */ + IO_PORT (SPI_MISO_IO) |= IO_BV (SPI_MISO_IO); + IO_DDR (SPI_MISO_IO) |= IO_BV (SPI_MISO_IO); + } +} + +void +spi_hard_send (uint8_t data) +{ + spi_hard_send_and_recv (data); +} + +uint8_t +spi_hard_recv (void) +{ + return spi_hard_send_and_recv (0); +} + +uint8_t +spi_hard_send_and_recv (uint8_t data) +{ + SPDR = data; + /* Wait the end of the transmission. */ + while (!(SPSR & _BV(SPIF))) + ; + /* Return data register. */ + return SPDR; +} + +#endif /* SPI0_DRIVER == SPI_DRIVER_HARD || SPI1_DRIVER == SPI_DRIVER_HARD */ -- cgit v1.2.3