ADS1299: ADS1299 Test Signal

Hello,Sir,

Finally I get the square-wave,but the image seems to have a lot of noise.(the first channel is seted  to normal electrode mode)

I found something wrong about my primary data get from the ADS1299.

Like the line I marked.

Why the data is wrong here? Is there some problem I ignored? Await your answer!

It sounds very resonable!

But when I change the SPI clock ,it looks like invalid! And I'm not clearly know how to decrease the delay between the time DRDY asserts and you begin reading data.

Even I set the channel power-down,the zero-line has fluctuation.

Here is my code,could help me check my code and point out my fault!

#include <ioCC2530.h>
#include <string.h>
#include "hal_cc8051.h"

#define LED1          P1_0
#define LED2          P1_1

#define SPI_DRDY      P1_2
#define CLKSEL        P1_3
#define SPI_START     P0_6
#define PWDN         P0_5
#define RESET        P0_4

#define LED_OFF 1
#define LED_ON  0
#define TX_SIZE 20
#define TEST_DATA "test uart"
char TxData[TX_SIZE];
void InitUart(void)
{ 
    PERCFG = 0x00;           //
    P0SEL = 0x0c;            //P0_2,P0_3
    P2DIR &= ~0xC0;          //P0 UART0
    
    U0CSR |= 0x80;           //UART
    U0GCR |= 11;				       
    U0BAUD |= 216;           //115200
    UTX0IF = 0;              
    LED2 = 1;
}

void UartSendString(char *Data, int len)
{
    int i;
    
    for(i=0; i<len; i++)
    {
        U0DBUF = *Data++;
        while(UTX0IF == 0);
        UTX0IF = 0;
    }
}

void WriteData(uint8 command)
{
    U1DBUF = command;
    while (!U1TX_BYTE);
    U1TX_BYTE = 0;        
}

char ReadData(uint8 value)
{
    U1DBUF = value;
    while (!U1TX_BYTE);
    
    //while (U1RX_BYTE);
    //U1RX_BYTE = 0;
    unsigned char temp = U1DBUF;
    U1TX_BYTE = 0;
    return temp; 
}

int spi_init()
{
    // SPI Master Mode
    PERCFG |= 0x02;        // map USART1 to its alternative 2 location. P1_4: SSN, P1_5: SCK, P1_6: MOSI, P1_7: MISO
    P1SEL |= 0xE0;        // P1_5, P1_6, and P1_7 are peripherals
    P1SEL &= ~0x10;        // P1_4 is GPIO (SSN)
    P1DIR |= 0x10;        // SSN is set as output
	
    U1BAUD = 0x00; U1GCR |= 0x0D;        // BAUD_M=0,BAUD_E=13,Fsck=250kHz.4us
    U1CSR &= ~0xA0;        // SPI Master Mode
    //        U1CSR &= ~0x80; U1CSR |= 0x20;        // SPI Slave Mode
    //U1GCR &= ~0xC0; U1GCR |= 0x20;        // MSB
    U1GCR = 0x6D;
        
    //IO_FUNC_PORT_PIN(1, 4, IO_FUNC_GIO);   
    IO_FUNC_PORT_PIN(1, 2, IO_FUNC_GIO);   
    IO_DIR_PORT_PIN(1, 2, IO_IN);  
    IO_FUNC_PORT_PIN(1, 3, IO_FUNC_GIO);   
    IO_DIR_PORT_PIN(1, 3, IO_IN); 
    IO_FUNC_PORT_PIN(0, 6, IO_FUNC_GIO);   
    IO_DIR_PORT_PIN(0, 6, IO_IN);
    
    IO_DIR_PORT_PIN(1, 4, IO_OUT); 
    IO_DIR_PORT_PIN(1, 5, IO_IN);  
    IO_DIR_PORT_PIN(1, 6, IO_OUT);   
    IO_DIR_PORT_PIN(1, 7, IO_IN);   
     
    IO_FUNC_PORT_PIN(1, 1, IO_FUNC_GIO);    //
    IO_DIR_PORT_PIN(1, 1, IO_OUT);          //
    IO_FUNC_PORT_PIN(1, 0, IO_FUNC_GIO);   
    IO_DIR_PORT_PIN(1, 0, IO_OUT);    
    return 0;
}

void main()
{
    char  temp[3];
    unsigned char  out[27];
    uint32 uartout[200];
    CLKCONCMD = 0x80; while (CLKCONSTA != 0x80);        // 32MHz
    InitUart(); 
    spi_init();
    LED1 = 1;
      
    P1_3 = 1;               //CLKSET = 1
    halMcuWaitUs(1000);
    P0_5 = 1;               //PWDN = 1
    
    P0_4 = 1;               //RESET pin =1
    
    //while(1){
    P1_4 = 0;               //SSN = 0;
    halMcuWaitUs(16);
    WriteData(0x06);        //RESET
    halMcuWaitUs(36);
    P1_4 = 1;
    halMcuWaitUs(16);
    P1_4 = 0;
    halMcuWaitUs(16);
    WriteData(0x11);       //SDATAC
    halMcuWaitUs(16);
    P1_4 = 1; 
    halMcuWaitUs(16);
    
    P1_4 = 0;
    halMcuWaitUs(16);
    WriteData(0x43);       //WREG and from 0x03h address    
    halMcuWaitUs(32);
    WriteData(0x00);       //only CONFOG3
    halMcuWaitUs(32);
    WriteData(0xE0);
    halMcuWaitUs(32);
    P1_4 = 1; 
    halMcuWaitUs(16);

    P1_4 = 0;
    halMcuWaitUs(16);
    WriteData(0x42);       //WREG and from 0x02h address    
    halMcuWaitUs(32);
    WriteData(0x00);       //only CONFOG2
    halMcuWaitUs(32);
    WriteData(0xD0);
    halMcuWaitUs(32);
    P1_4 = 1; 
    halMcuWaitUs(16);
    
    P1_4 = 0;
    halMcuWaitUs(16);
    WriteData(0x45);       //WREG and from 0x05h address    
    halMcuWaitUs(32);
    WriteData(0x07);       //eight channels | CHnSET
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    WriteData(0x05);
    halMcuWaitUs(32);
    P1_4 = 1;
    halMcuWaitUs(16);
    //P0_6 = 1;              //START=1
    //halMcuWaitUs(4);
    
    P1_4 = 0;
    halMcuWaitUs(16);
    WriteData(0x10);       //Come back to RDATAC Mode 
    //halMcuWaitUs(16);     
    P1_4 = 1;
    P0_6 = 1;              //START=1
    while(1)
    {
      if(P1_2 == 0){
        for(int i=0;i<27;i++){
          //for(int j=0;i<3;j++){
            P1_4 = 0;
            U1DBUF = 0x00;
            while(!U1TX_BYTE);
            //temp[j] = U1DBUF;
            out[i] = U1DBUF;
            P1_4 = 1;
            U1TX_BYTE = 0;
          //}
          //out[i] = temp[0]+temp[1]+temp[2];
          //uartout[i]=hexStr2Str(out);
          
          //sprintf(uartout[i],"%6X",out);
        }
       //out[27] = 0xFF;
       UartSendString(out,27);
       halMcuWaitMs(100);
      }
    }
    //read register
    /*P1_4 = 0; 
    halMcuWaitUs(4);
    WriteData(0x20);       //RREG two 8-bit(command+address)
    halMcuWaitUs(13);
    WriteData(0x00);       //the number of registers
    halMcuWaitUs(13);
    temp[0] = ReadData(0x00);
    /*temp[1] = ReadData(0x00);
    temp[2] = ReadData(0x00);
    temp[3] = ReadData(0x00);
    temp[4] = ReadData(0x00);
    temp[5] = ReadData(0x00);
    temp[6] = ReadData(0x00);
    temp[7] = ReadData(0x00);
    temp[8] = ReadData(0x00);
    temp[9] = ReadData(0x00);
    temp[10] = ReadData(0x00);
    temp[11] = ReadData(0x00);
    temp[12] = ReadData(0x00);
    temp[13] = ReadData(0x00);
    temp[14] = ReadData(0x00);
    temp[15] = ReadData(0x00);
    temp[16] = ReadData(0x00);
    temp[17] = ReadData(0x00);
    temp[18] = ReadData(0x00);
    temp[19] = ReadData(0x00);
    temp[20] = ReadData(0x00);
    temp[21] = ReadData(0x00);
    temp[22] = ReadData(0x00);
    temp[23] = ReadData(0x00);
    halMcuWaitUs(9);
    P1_4 = 1;
    //int i=500;
    while(1)
    {
    UartSendString(temp,1); //
    halMcuWaitMs(100);                 //
    //}
    //i--;
    }*/
        
}

Hello,sir.

Finally I get the square-wave,but mine is different from the datasheet and others' .

A cycle of mine is just less than 10 sampling points.The datasheet is almost 120.

That's why? I wonder the problem is my delay before my 8 channels' data reading or not.

Please give me some advice.

 Wait for your reply.