spi1 and dac1 conflict

[boris239955_st]

Posted on September 18, 2011 at 22:38

I have observed a conflict between SPI1 and DAC1 on stm32f103ZG micro.

When spi1 is initialized first and then DAC1 the spi1 clock shuts down. It is time sensitive, but I manage to make repeatable on stm3210E-EVAL board. Common scenario is: nw_spi_init(SPI_1);   nw_spi_send_32(SPI_1, 0xffffffff);   nw_spi_send_32(SPI_1, 0xffffffff);   for(i=0;i<0x1f;i++);   nw_dac_config();//error is caused here spi1 clk shuts down by dac1 if dac is enabled   for(i=0;i<0x2f;i++);   nw_spi_send_32(SPI_1, 0xffffffff);   nw_spi_send_32(SPI_1, 0xffffffff); SPI1 configuration is:

GPIO_InitTypeDef

gpioInitStruct;

 SPI_InitTypeDef

spiInitStruct;

 RCC_APB2PeriphClockCmd

(RCC_APB2Periph_AFIO ,

ENABLE

);

//

RCC_APB2PeriphClockCmd

((RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOG | RCC_APB2Periph_SPI1),

ENABLE

);

 gpioInitStruct.

GPIO_Speed

=

GPIO_Speed_50MHz

;

 gpioInitStruct.

GPIO_Mode

=

GPIO_Mode_Out_PP

;

 gpioInitStruct.

GPIO_Pin

= GPIO_Pin_8;

 GPIO_Init(GPIOG, &gpioInitStruct);

SPI1_OUTPUT_EXTENDER_SW_CS_HIGH();

 gpioInitStruct.

GPIO_Mode

=

GPIO_Mode_AF_PP

;

 gpioInitStruct.

GPIO_Pin

= GPIO_Pin_5;//clock

 GPIO_Init(GPIOA, &gpioInitStruct);

 gpioInitStruct.

GPIO_Pin

= GPIO_Pin_7;//mosi

 GPIO_Init(GPIOA, &gpioInitStruct);

 gpioInitStruct.

GPIO_Pin

= GPIO_Pin_6;//miso

 gpioInitStruct.

GPIO_Mode

=

GPIO_Mode_IN_FLOATING

;

 GPIO_Init(GPIOA, &gpioInitStruct);

 spiInitStruct.

SPI_Direction

= SPI_Direction_2Lines_FullDuplex;

 spiInitStruct.

SPI_Mode

= SPI_Mode_Master;

 spiInitStruct.

SPI_DataSize

= SPI_DataSize_16b;

 spiInitStruct.

SPI_CPOL

= SPI_CPOL_Low;

// idle low

 spiInitStruct.

SPI_CPHA

= SPI_CPHA_1Edge;

//data captured on leading rising edge

 spiInitStruct.

SPI_NSS

= SPI_NSS_Soft;

// software driven with external pin CS low active

 spiInitStruct.

SPI_FirstBit

= SPI_FirstBit_MSB;

 spiInitStruct.

SPI_CRCPolynomial

= 7;

//not used

 spiInitStruct.

SPI_BaudRatePrescaler

= SPI_BaudRatePrescaler_8;

 SPI_I2S_DeInit(SPI1);

 SPI_Init(SPI1, &spiInitStruct);

 SPI_Cmd(SPI1,

ENABLE

); The dac1 configuration is:

static

void

nw_dac_config

(

void

)

{

GPIO_InitTypeDef

  GPIO_InitStructure;

DAC_InitTypeDef

   DAC_InitStructure;

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,

ENABLE

);

   GPIO_InitStructure.

GPIO_Pin

= GPIO_Pin_4;

   GPIO_InitStructure.

GPIO_Mode

=

GPIO_Mode_AIN

;

   GPIO_Init(GPIOA, &GPIO_InitStructure);

/* DAC channel1 Configuration */

    DAC_InitStructure.

DAC_Trigger

= DAC_Trigger_Software;

    DAC_InitStructure.

DAC_WaveGeneration

= DAC_WaveGeneration_None;

    DAC_InitStructure.

DAC_OutputBuffer

= DAC_OutputBuffer_Enable;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC,

ENABLE

);

    DAC_Init(DAC_Channel_1, &DAC_InitStructure);

/* Set DAC Channel1 DHR12L register */

    DAC_SetChannel1Data(DAC_Align_12b_R, 0x7FF);

}

//-------------

static

void

nw_dac_start

(

u16

voltage)

//mV

{

#define

NW_ADC_VREF_mV   ((u16)3000)

#define

NW_ADC_COUNT_MAX   ((u16)4095)

u32

data = (voltage > NW_ADC_VREF_mV ?  NW_ADC_VREF_mV : voltage) * NW_ADC_COUNT_MAX;

//enable DAC channel

  DAC->

CR

|= (DAC_CR_EN1 << DAC_Channel_1);

  DAC_SetChannel1Data(DAC_Align_12b_R, (

u16

)(data / NW_ADC_VREF_mV));

/* Start DAC Channel1 conversion by software */

  DAC_SoftwareTriggerCmd(DAC_Channel_1,

ENABLE

);

}

Has anyone experienced similar problems?