STM32 SPI 连接 EPM240T100C5N 数据不稳定

只看该作者 · 2020-1-13 21:09

发送和接受到的数据经常错位或卡顿导致不稳定
STM32F103VE SPI 速度 9M
EPM240T100C5N 时钟 50M
应该时 CPLD SPI 接口程序问题各位大哥帮忙看看

/***********************************************************************
　　 ****************** name：SPI_Slaver_Driver **************
　　       ********** author：made by zzuxzt **********
　　 ****************** time：2014.4.29 **********************
***********************************************************************/
//use SPI 3 mode,CHOL = 1,CHAL = 1
module spi( input clk,
input rst_n,
input CS_N,
input SCK,
input MOSI,
output reg MISO,
input [7:0] txd_data,
output reg [7:0] rxd_data,
output rxd_flag); /*recieve done,please transmit data*/

//-------------------------capture the sck-----------------------------
reg sck_r0,sck_r1;
wire sck_n,sck_p;
always@(posedge clk or negedge rst_n)
begin
if(!rst_n)
      begin
         sck_r0 <= 1'b1; //sck of the idle state is high
         sck_r1 <= 1'b1;
      end
else
      begin
         sck_r0 <= SCK;
         sck_r1 <= sck_r0;
      end
end

assign sck_n = (~sck_r0 & sck_r1)? 1'b1:1'b0; //capture the sck negedge
assign sck_p = (~sck_r1 & sck_r0)? 1'b1:1'b0; //capture the sck posedge

//-----------------------spi_slaver read data-------------------------------
reg rxd_flag_r;
reg [2:0] rxd_state;
always@(posedge clk or negedge rst_n)
begin
if(!rst_n)
      begin
         rxd_data <= 1'b0;
         rxd_flag_r <= 1'b0;
         rxd_state <= 1'b0;
      end
else if(sck_p && !CS_N)
      begin
         case(rxd_state)
            3'd0:begin
                     rxd_data[7] <= MOSI;
                     rxd_flag_r <= 1'b0; //reset rxd_flag
                     rxd_state <= 3'd1;
                  end
            3'd1:begin
                     rxd_data[6] <= MOSI;
                     rxd_state <= 3'd2;
                  end
            3'd2:begin
                     rxd_data[5] <= MOSI;
                     rxd_state <= 3'd3;
                  end
            3'd3:begin
                     rxd_data[4] <= MOSI;
                     rxd_state <= 3'd4;
                  end
            3'd4:begin
                     rxd_data[3] <= MOSI;
                     rxd_state <= 3'd5;
                  end
            3'd5:begin
                     rxd_data[2] <= MOSI;
                     rxd_state <= 3'd6;
                  end
            3'd6:begin
                     rxd_data[1] <= MOSI;
                     rxd_state <= 3'd7;
                  end
            3'd7:begin
                     rxd_data[0] <= MOSI;
                     rxd_flag_r <= 1'b1;  //set rxd_flag
                     rxd_state <= 3'd0;
                  end
            default: ;
         endcase
      end
end

//--------------------capture spi_flag posedge--------------------------------
reg rxd_flag_r0,rxd_flag_r1;
always@(posedge clk or negedge rst_n)
begin
if(!rst_n)
      begin
         rxd_flag_r0 <= 1'b0;
         rxd_flag_r1 <= 1'b0;
      end
else
      begin
         rxd_flag_r0 <= rxd_flag_r;
         rxd_flag_r1 <= rxd_flag_r0;
      end
end

assign rxd_flag = (~rxd_flag_r1 & rxd_flag_r0)? 1'b1:1'b0;

//---------------------spi_slaver send data---------------------------
reg [2:0] txd_state;
always@(posedge clk or negedge rst_n)
begin
if(!rst_n)
      begin
         txd_state <= 1'b0;
      end
else if(sck_n && !CS_N)
      begin
         case(txd_state)
            3'd0:begin
                     MISO <= txd_data[7];
                     txd_state <= 3'd1;
                  end
            3'd1:begin
                     MISO <= txd_data[6];
                     txd_state <= 3'd2;
                  end
            3'd2:begin
                     MISO <= txd_data[5];
                     txd_state <= 3'd3;
                  end
            3'd3:begin
                     MISO <= txd_data[4];
                     txd_state <= 3'd4;
                  end
            3'd4:begin
                     MISO <= txd_data[3];
                     txd_state <= 3'd5;
                  end
            3'd5:begin
                     MISO <= txd_data[2];
                     txd_state <= 3'd6;
                  end
            3'd6:begin
                     MISO <= txd_data[1];
                     txd_state <= 3'd7;
                  end
            3'd7:begin
                     MISO <= txd_data[0];
                     txd_state <= 3'd0;
                  end
            default: ;
         endcase
      end
end

endmodule

只看该作者 · 2020-1-13 21:11

STM32

void SPI3_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
SPI_InitTypeDef  SPI_InitStructure;

RCC_APB2PeriphClockCmd( SPI3_PORT_RCC , ENABLE );
RCC_APB1PeriphClockCmd(SPI3_RCC,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);

GPIO_InitStructure.GPIO_Pin = SPI3_CLK_PIN | SPI3_MOSI_PIN | SPI3_MISO_PIN;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //复用推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(SPI3_CLK_PORT, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = SPI_CS_PIN;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(SPI_CS_PORT, &GPIO_InitStructure);

GPIO_SetBits(SPI3_CLK_PORT,SPI3_CLK_PIN|SPI3_MOSI_PIN|SPI3_MISO_PIN|SPI_CS_PIN);

SPI_InitStructure.SPI_Direction       = SPI_Direction_2Lines_FullDuplex;  //设置SPI单向或者双向的数据模式:SPI设置为双线双向全双工
SPI_InitStructure.SPI_Mode             = SPI_Mode_Master; //设置SPI工作模式:设置为主SPI
SPI_InitStructure.SPI_DataSize       = SPI_DataSize_8b; //设置SPI的数据大小:SPI发送接收8位帧结构
SPI_InitStructure.SPI_CPOL             = SPI_CPOL_High; //选择了串行时钟的稳态:时钟悬空高
SPI_InitStructure.SPI_CPHA             = SPI_CPHA_2Edge; //数据捕获于第二个时钟沿
SPI_InitStructure.SPI_NSS             = SPI_NSS_Soft; //NSS信号由硬件（NSS管脚）还是软件（使用SSI位）管理:内部NSS信号有SSI位控制
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4; //定义波特率预分频的值:波特率预分频值为256
SPI_InitStructure.SPI_FirstBit       = SPI_FirstBit_MSB; //指定数据传输从MSB位还是LSB位开始:数据传输从MSB位开始
SPI_InitStructure.SPI_CRCPolynomial    = 7; //CRC值计算的多项式
SPI_Init(SPI3, &SPI_InitStructure);  //根据SPI_InitStruct中指定的参数初始化外设SPIx寄存器

SPI_Cmd(SPI3, ENABLE); //使能SPI外设

// SPI1_ReadWriteByte(0xff);//启动传输
}

//SPIx 读写一个字节
//TxData:要写入的字节
//返回值:读取到的字节
u8 SPI3_ReadWriteByte(u8 TxData)
{
u8 retry=0;
while (SPI_I2S_GetFlagStatus(SPI3, SPI_I2S_FLAG_TXE) == RESET) //检查指定的SPI标志位设置与否:发送缓存空标志位
{
retry++;
if(retry>200)return 0;
}
SPI_I2S_SendData(SPI3, TxData); //通过外设SPIx发送一个数据
retry=0;

while (SPI_I2S_GetFlagStatus(SPI3, SPI_I2S_FLAG_RXNE) == RESET)//检查指定的SPI标志位设置与否:接受缓存非空标志位
{
retry++;
if(retry>200)return 0;
}
return SPI_I2S_ReceiveData(SPI3); //返回通过SPIx最近接收的数据
}