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-rw-r--r--digital/avr/modules/spi/spi.avr.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/digital/avr/modules/spi/spi.avr.c b/digital/avr/modules/spi/spi.avr.c
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+++ b/digital/avr/modules/spi/spi.avr.c
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+/* spi.avr.c */
+/* {{{
+ *
+ * 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 "io.h"
+#include "common.h"
+#include "spi.h"
+
+/** For host */
+#ifdef HOST
+static uint8_t SPCR;
+static uint8_t SPDR;
+static uint8_t SPSR;
+static uint8_t SPIF;
+#endif
+
+/** Spi driver context. */
+static spi_t spi_global;
+
+/** Initialise the SPI Control Register.
+ * \param sprc the sprc register data to be store in the register.
+ * \param cb the function call back to call the user which receive the data.
+ * \param user_data the user data to be provieded in the function call back.
+ */
+void
+spi_init(uint8_t sprc)
+{
+ /* Master configuration. */
+ if (sprc & _BV(MSTR))
+ {
+ SPI_PORT |= _BV(SPI_BIT_SS);
+ SPI_DDR |= _BV(SPI_BIT_SS);
+
+ SPI_DDR &= ~_BV(SPI_BIT_MISO);
+ SPI_PORT &= ~_BV(SPI_BIT_MISO);
+
+ SPI_PORT |= _BV(SPI_BIT_MOSI);
+ SPI_DDR |= _BV(SPI_BIT_MOSI);
+
+ SPI_PORT |= _BV(SPI_BIT_SCK);
+ SPI_DDR |= _BV(SPI_BIT_SCK);
+ }
+ else
+ {
+ SPI_DDR &= ~_BV(SPI_BIT_SS);
+ SPI_PORT |= _BV(SPI_BIT_SS);
+
+ SPI_PORT |= _BV(SPI_BIT_MISO);
+ SPI_DDR |= _BV(SPI_BIT_MISO);
+
+ SPI_DDR &= ~_BV(SPI_BIT_MOSI);
+ SPI_PORT &= ~_BV(SPI_BIT_MOSI);
+
+ SPI_DDR &= ~_BV(SPI_BIT_SCK);
+ SPI_PORT &= ~_BV(SPI_BIT_SCK);
+ }
+
+ SPCR = sprc;
+ spi_global.interruption = SPCR & _BV(SPIE);
+}
+
+/** Send a data to the Slave.
+ * \param data the data to send
+ */
+void
+spi_send(uint8_t data)
+{
+ SPDR = data;
+ // Wait the end of the transmission.
+ while(!(SPSR & _BV(SPIF)));
+}
+
+/** Receive a data from the SPI bus.
+ * \return the data received from the bus.
+ */
+uint8_t
+spi_recv(void)
+{
+ SPDR = 0;
+ /* Wait for reception complete */
+ while(!(SPSR & _BV(SPIF)));
+
+ /* Return data register */
+ return SPDR;
+}
+
+/** Send and receive data.
+ * \param data the data to send.
+ * \return the data received.
+ */
+uint8_t
+spi_send_and_recv (uint8_t data)
+{
+ SPDR = data;
+ // Wait the end of the transmission.
+ while(!(SPSR & _BV(SPIF)));
+
+ return SPDR;
+}
+
+/** Return the status register from the SPI driver.
+ * \return the status register value
+ */
+uint8_t
+spi_status(void)
+{
+ return SPSR;
+}
+