spi_sam7x.c

keil arm flash fs 最新版 在Ｋｅｉｌ ａｒｍ下使用

/*----------------------------------------------------------------------------
 *      R T L  -  F l a s h   F i l e   S y s t e m
 *----------------------------------------------------------------------------
 *      Name:    SPI_SAM7X.C 
 *      Purpose: Serial Peripheral Interface Driver for AT91SAM7X
 *      Rev.:    V3.22
 *----------------------------------------------------------------------------
 *      This code is part of the RealView Run-Time Library.
 *      Copyright (c) 2004-2008 KEIL - An ARM Company. All rights reserved.
 *---------------------------------------------------------------------------*/

#include <File_Config.h>
#include <AT91SAM7X256.H>               /* AT91SAM7X256 definitions          */
#include <lib_AT91SAM7X256.h>


/*----------------------------------------------------------------------------
 *      SPI Driver Functions
 *----------------------------------------------------------------------------
 *  Required functions for SPI driver module:
 *   - void spi_init ()
 * no DMA:
 *   - void spi_ss   (U32 ss)
 *   - U8   spi_send (U8 outb)
 * with DMA:
 *   - void spi_command ()
 *---------------------------------------------------------------------------*/

/*--------------------------- spi_init --------------------------------------*/

void spi_init (void) {
  /* Initialize and enable the SSP Interface module */

   /* Enable Clocks */
   AT91F_PMC_EnablePeriphClock (AT91C_BASE_PMC, (1 << AT91C_ID_PIOA) |
                                                (1 << AT91C_ID_SPI0));

  /* SPI0_MISO, SPI0_MOSI, SPI0_SPCK are SPI0_NPCS0 pins */
   AT91F_PIO_CfgPeriph (AT91C_BASE_PIOA, AT91C_PA16_SPI0_MISO | 
                                         AT91C_PA17_SPI0_MOSI |
                                         AT91C_PA18_SPI0_SPCK | 
                                         AT91C_PA12_SPI0_NPCS0, 0);
   /* Initialize SPI0 Controller */
   AT91F_SPI_Reset (AT91C_BASE_SPI0);
   AT91F_SPI_CfgMode (AT91C_BASE_SPI0, AT91C_SPI_MSTR | AT91C_SPI_MODFDIS);

   /* Set DLYBCT = 0(10ns), DLYBS = 15(300ns), SBCR = 3(16MHz SPI clock) */
   AT91F_SPI_CfgCs (AT91C_BASE_SPI0, 0, AT91C_SPI_CPOL | AT91C_SPI_BITS_8 |
                                        (0 << 24) | (15 << 16) | (3 << 8));
   /* Use NPCS0 as chip select. */
   AT91F_SPI_CfgPCS (AT91C_BASE_SPI0, 0x0E);
   AT91F_SPI_Enable (AT91C_BASE_SPI0);
}


/*--------------------------- spi_command -----------------------------------*/

void spi_command (U8 *cmd, U8 *tbuf, U8 *rbuf, U32 sz) {
  /* Write and Read a byte on SPI interface */

   AT91C_BASE_SPI0->SPI_RPR  = (U32)&cmd[1];
   AT91C_BASE_SPI0->SPI_RCR  = cmd[0];
   AT91C_BASE_SPI0->SPI_RNPR = (U32)rbuf;
   AT91C_BASE_SPI0->SPI_RNCR = sz;

   AT91C_BASE_SPI0->SPI_TPR  = (U32)&cmd[1];
   AT91C_BASE_SPI0->SPI_TCR  = cmd[0];
   AT91C_BASE_SPI0->SPI_TNPR = (U32)tbuf;
   AT91C_BASE_SPI0->SPI_TNCR = sz;

   /* Start SPI DMA Transfer. */
   AT91C_BASE_SPI0->SPI_PTCR = AT91C_PDC_TXTEN | AT91C_PDC_RXTEN;

   while (!(AT91C_BASE_SPI0->SPI_SR & AT91C_SPI_TXEMPTY));

   AT91C_BASE_SPI0->SPI_PTCR = AT91C_PDC_TXTDIS | AT91C_PDC_RXTDIS;
}


/*----------------------------------------------------------------------------
 * end of file
 *---------------------------------------------------------------------------*/