Beispiel #1
0
/**
 * \brief Initialize SPI as master.
 */
static void spi_master_initialize(void)
{
	/* Configure an SPI peripheral. */
	uint32_t spi_chip_sel, spi_clk_freq, spi_clk_pol, spi_clk_pha;
	spi_enable_clock(SPI_MASTER_BASE);
	spi_reset(SPI_MASTER_BASE);
	spi_set_master_mode(SPI_MASTER_BASE);
	spi_disable_mode_fault_detect(SPI_MASTER_BASE);
	spi_disable_loopback(SPI_MASTER_BASE);

	spi_set_peripheral_chip_select_value(SPI_MASTER_BASE, spi_get_pcs(2));	// This sets the value of PCS within the Mode Register.
	spi_set_variable_peripheral_select(SPI_MASTER_BASE);					// PCS needs to be set within each transfer (PCS within SPI_TDR).
	spi_disable_peripheral_select_decode(SPI_MASTER_BASE);					// Each CS is to be connected to a single device.
	spi_set_delay_between_chip_select(SPI_MASTER_BASE, SPI_DLYBCS);

	/* Set communication parameters for CS0	*/
	spi_chip_sel = 0;
	spi_clk_freq = 100000;	// SPI CLK for RTC = 100kHz.
	spi_clk_pol = 1;
	spi_clk_pha = 0;
	spi_set_transfer_delay(SPI_MASTER_BASE, spi_chip_sel, SPI_DLYBS,
			SPI_DLYBCT);
	spi_set_bits_per_transfer(SPI_MASTER_BASE, spi_chip_sel, SPI_CSR_BITS_16_BIT);
	spi_set_baudrate_div(SPI_MASTER_BASE, spi_chip_sel, spi_calc_baudrate_div(spi_clk_freq, sysclk_get_cpu_hz())); 
	spi_configure_cs_behavior(SPI_MASTER_BASE, spi_chip_sel, SPI_CS_RISE_FORCED);		// CS rises after SPI transfers have completed.
	spi_set_clock_polarity(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pol);
	spi_set_clock_phase(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pha);
	
	/* Set communication parameters for CS1	*/
	spi_chip_sel = 1;
	spi_clk_freq = 2000000;	// SPI CLK for RTC = 4MHz.
	spi_clk_pol = 0;
	spi_clk_pha = 0;
	spi_set_transfer_delay(SPI_MASTER_BASE, spi_chip_sel, SPI_DLYBS,
	SPI_DLYBCT);
	spi_set_bits_per_transfer(SPI_MASTER_BASE, spi_chip_sel, SPI_CSR_BITS_8_BIT);
	spi_set_baudrate_div(SPI_MASTER_BASE, spi_chip_sel, spi_calc_baudrate_div(spi_clk_freq, sysclk_get_cpu_hz())); 
	spi_configure_cs_behavior(SPI_MASTER_BASE, spi_chip_sel, SPI_CS_RISE_FORCED);
	spi_set_clock_polarity(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pol);
	spi_set_clock_phase(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pha);
	
	/* Set communication parameters for CS2	*/
	spi_chip_sel = 2;
	spi_clk_freq = 44000000;	// SPI CLK for MEM2 = 44MHz.
	spi_clk_pol = 1;
	spi_clk_pha = 0;
	spi_set_transfer_delay(SPI_MASTER_BASE, spi_chip_sel, SPI_DLYBS,
	SPI_DLYBCT);
	spi_set_bits_per_transfer(SPI_MASTER_BASE, spi_chip_sel, SPI_CSR_BITS_8_BIT);
	spi_set_baudrate_div(SPI_MASTER_BASE, spi_chip_sel, spi_calc_baudrate_div(spi_clk_freq, sysclk_get_cpu_hz()));
	spi_configure_cs_behavior(SPI_MASTER_BASE, spi_chip_sel, SPI_CS_KEEP_LOW);
	spi_set_clock_polarity(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pol);
	spi_set_clock_phase(SPI_MASTER_BASE, spi_chip_sel, spi_clk_pha);
	
	/* Enable SPI Communication */
	spi_enable(SPI_MASTER_BASE);
}
Beispiel #2
0
/**
 * \brief Set up an SPI device.
 *
 * The returned device descriptor structure must be passed to the driver
 * whenever that device should be used as current slave device.
 *
 * \param p_spi     Base address of the SPI instance.
 * \param device    Pointer to SPI device struct that should be initialized.
 * \param flags     SPI configuration flags. Common flags for all
 *                  implementations are the SPI modes SPI_MODE_0 ...
 *                  SPI_MODE_3.
 * \param baud_rate Baud rate for communication with slave device in Hz.
 * \param sel_id    Board specific select id.
 */
void spi_master_setup_device(Spi *p_spi, struct spi_device *device,
                             spi_flags_t flags, uint32_t baud_rate, board_spi_select_id_t sel_id)
{
    sel_id = sel_id;

    spi_set_transfer_delay(p_spi, device->id, CONFIG_SPI_MASTER_DELAY_BS,
                           CONFIG_SPI_MASTER_DELAY_BCT);
    spi_set_bits_per_transfer(p_spi, device->id,
                              CONFIG_SPI_MASTER_BITS_PER_TRANSFER);
    spi_set_baudrate_div(p_spi, device->id,
                         spi_calc_baudrate_div(baud_rate, sysclk_get_cpu_hz()));
    spi_configure_cs_behavior(p_spi, device->id, SPI_CS_KEEP_LOW);
    spi_set_clock_polarity(p_spi, device->id, flags >> 1);
    spi_set_clock_phase(p_spi, device->id, ((flags & 0x1) ^ 0x1));
}
Beispiel #3
0
/**
 * \brief Set up an SPI device.
 *
 * The returned device descriptor structure must be passed to the driver
 * whenever that device should be used as current slave device.
 *
 * \param p_spi     Base address of the SPI instance.
 * \param device    Pointer to SPI device struct that should be initialized.
 * \param flags     SPI configuration flags. Common flags for all
 *                  implementations are the SPI modes SPI_MODE_0 ...
 *                  SPI_MODE_3.
 * \param baud_rate Baud rate for communication with slave device in Hz.
 * \param sel_id    Board specific select id.
 */
void spi_master_setup_device(Spi *p_spi, struct spi_device *device,
                             spi_flags_t flags, uint32_t baud_rate, board_spi_select_id_t sel_id)
{
    int16_t baud_div = spi_calc_baudrate_div(baud_rate, sysclk_get_cpu_hz());
    /* avoid Cppcheck Warning */
    UNUSED(sel_id);
    if (-1 == baud_div) {
        Assert(0 == "Failed to find baudrate divider");
    }
    spi_set_transfer_delay(p_spi, device->id, CONFIG_SPI_MASTER_DELAY_BS,
                           CONFIG_SPI_MASTER_DELAY_BCT);
    spi_set_bits_per_transfer(p_spi, device->id,
                              CONFIG_SPI_MASTER_BITS_PER_TRANSFER);
    spi_set_baudrate_div(p_spi, device->id, baud_div);
    spi_configure_cs_behavior(p_spi, device->id, SPI_CS_KEEP_LOW);
    spi_set_clock_polarity(p_spi, device->id, flags >> 1);
    spi_set_clock_phase(p_spi, device->id, ((flags & 0x1) ^ 0x1));
}
Beispiel #4
0
/**
 * \brief Set up an SPI device.
 *
 * The returned device descriptor structure must be passed to the driver
 * whenever that device should be used as current slave device.
 *
 * \param p_spi     Base address of the SPI instance.
 * \param device    Pointer to SPI device struct that should be initialized.
 * \param flags     SPI configuration flags. Common flags for all
 *                  implementations are the SPI modes SPI_MODE_0 ...
 *                  SPI_MODE_3.
 * \param baud_rate Baud rate for communication with slave device in Hz.
 * \param sel_id    Board specific select id.
 */
void spi_master_setup_device(Spi *p_spi, const struct spi_device *device,
		spi_flags_t flags, uint32_t baud_rate, board_spi_select_id_t sel_id)
{
	/* avoid Cppcheck Warning */
	UNUSED(sel_id);
	UNUSED(flags);

	spi_reset(p_spi);
	spi_set_transfer_delay(p_spi, device->id, CONFIG_SPI_MASTER_DELAY_BS,
			CONFIG_SPI_MASTER_DELAY_BCT);
	spi_set_bits_per_transfer(p_spi, device->id,
			CONFIG_SPI_MASTER_BITS_PER_TRANSFER);
	int16_t baud_div = spi_calc_baudrate_div(baud_rate, SystemCoreClock);
	spi_set_baudrate_div(p_spi, device->id, baud_div);
	spi_configure_cs_behavior(p_spi, device->id, SPI_CS_KEEP_LOW);
	spi_set_clock_polarity(p_spi, device->id, flags >> 1);
	spi_set_clock_phase(p_spi, device->id, ((flags & 0x1) ^ 0x1));
}
/** Set the SPI baud rate
 *
 * Actual frequency may differ from the desired frequency due to available dividers and bus clock
 * Configures the SPI peripheral's baud rate
 * @param[in,out] obj The SPI object to configure
 * @param[in]     hz  The baud rate in Hz
 */
void spi_frequency(spi_t *obj, int hz){
	spi_disable(obj->spi.spi_base);	
	int16_t baudrate_div=spi_calc_baudrate_div(hz, sysclk_get_cpu_hz());
	spi_set_baudrate_div(obj->spi.spi_base,obj->spi.cs,(uint8_t)baudrate_div);
	spi_enable(obj->spi.spi_base);
}