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Diffstat (limited to 'digital/avr/modules/spi/spi_hard.avr.c')
-rw-r--r--digital/avr/modules/spi/spi_hard.avr.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/digital/avr/modules/spi/spi_hard.avr.c b/digital/avr/modules/spi/spi_hard.avr.c
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+++ b/digital/avr/modules/spi/spi_hard.avr.c
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+/* 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 */