AFE4490: ATE4490 SPI does not read

Hello Farid Mabrouk,

1) Pin 20 is ADE_PDN
2) Pin 29 is RESET
3) If Diagnostic bit (DIAG_EN) is set (0x00[2:2]), the ADC data are invalid because of toggling diagnostics switches.
4) If Software Reset bit (SW_RST) is set (0x00[3:3]), Software reset applied. Resets all internal registers to the default values and self-clearsto '0'

Regards,

Midhun Raveendran

Hello Farid Mabrouk,

  Inorder to read from Any register, you need to set the SPI_READ bit.

Regards,

Midhun Raveendran

Thank you all for your reply. I managed to fix the issue. I have to send 32 bits per frame. I was sending one byte at a time( CS needs to be low for the entire 4 bytes).

I have another issue now: I am reading reasonable values for LED1VAL. However, I am reading 0x1FFF19 value all the time from LED2VAL register. I suspect this has to do with my default settings. Could anyone look at my settings below and tell me if they are right?

static uint32_t AFE4490DefaultsRegs[49]= {
    //Reg0: CONTROL0: CONTROL REGISTER 0
    0x00000,
       //Reg1:REDSTARTCOUNT: SAMPLE RED START COUNT
    6000,
        //Reg2:REDENDCOUNT: SAMPLE RED END COUNT
    7599,
        //Reg3:REDLEDSTARTCOUNT: RED LED START COUNT
    6000,
        //Reg4:REDLEDENDCOUNT: RED LED END COUNT
    7599,
    //Reg5:AMBREDSTARTCOUNT: SAMPLE AMBIENT RED START COUNT
    0000,
    //Reg6:AMBREDENDCOUNT: SAMPLE AMBIENT RED END COUNT
    1599,
    //Reg7:IRSTARTCOUNT: SAMPLE IR START COUNT
    2000,
        //Reg8:IRENDCOUNT: SAMPLE IR END COUNT
    3599,
        //Reg9:IRLEDSTARTCOUNT: IR LED START COUNT
    2000,
    //Reg10:IRLEDENDCOUNT: IR LED END COUNT
    3599,
    //Reg11:AMBIRSTARTCOUNT: SAMPLE AMBIENT IR START COUNT
    4000,
        //Reg12:AMBIRENDCOUNT: SAMPLE AMBIENT IR END COUNT
    5599,
    //Reg13:REDCONVSTART: REDCONVST
    2,
    //Reg14:REDCONVEND: RED CONVERT END COUNT
    1999,
    //Reg15:AMBREDCONVSTART: RED AMBIENT CONVERT START COUNT
    2002,
    //Reg16:AMBREDCONVEND: RED AMBIENT CONVERT END COUNT
    3999,
    //Reg17:IRCONVSTART: IR CONVERT START COUNT
    4002,
    //Reg18:IRCONVEND: IR CONVERT END COUNT
    5999,
    //Reg19:AMBIRCONVSTART: IR AMBIENT CONVERT START COUNT
    6002,
    //Reg20:AMBIRCONVEND: IR AMBIENT CONVERT END COUNT
    7999,
    //Reg21:ADCRESETSTCOUNT0: ADC RESET 0 START COUNT
    0,
    //Reg22:ADCRESETENDCOUNT0: ADC RESET 0 END COUNT
    0,
    //Reg23:ADCRESETSTCOUNT1: ADC RESET 1 START COUNT
    2000,
    //Reg24:ADCRESETENDCOUNT1: ADC RESET 1 END COUNT
    2000,
    //Reg25:ADCRESETENDCOUNT2: ADC RESET 2 START COUNT
    4000,
    //Reg26:ADCRESETENDCOUNT2: ADC RESET 2 END COUNT
    4000,
    //Reg27:ADCRESETENDCOUNT3: ADC RESET 3 START COUNT
    6000,
    //Reg28:ADCRESETENDCOUNT3: ADC RESET 3 END COUNT
    6000,
    //Reg29:PRPCOUNT: PULSE REPETITION PERIOD COUNT  By default it is: 7999
    20000,
    //Reg30:CONTROL1: CONTROL REGISTER 1
    0x00107,  //timer enabled, averages=3, RED and IR LED pulse ON PD_ALM AND LED_ALM pins
    //Reg31:?: ??
    0x00000,
    //Reg32:TIAGAIN: TRANS IMPEDANCE AMPLIFIER GAIN SETTING REGISTER
    0x00000,
    //Reg33:TIA_AMB_GAIN: TRANS IMPEDANCE AAMPLIFIER AND AMBIENT CANELLATION STAGE GAIN
    0x00000,
     //Reg34:LEDCNTRL: LED CONTROL REGISTER
    0x11414,
    //Reg35:CONTROL2: CONTROL REGISTER 2
    0x00000, //bit 9
    //Reg36:?: ??
    0x00000,
    //Reg37:?: ??
    0x00000,
    //Reg38:?: ??
    0x00000,
     //Reg39:?: ??
    0x00000,
     //Reg40:: ??
    0x00000,
    //Reg41:ALARM: ??
    0x00000,
    //Reg42:REDVALUE: RED DIGITAL SAMPLE VALUE
    0x00000,
    //Reg43:AMBREDVALUE: Ambient RED Digital Sample Value
    0x00000,
    //Reg44:IRVALUE: IR Digital Sample Value
    0x00000,
    //Reg45:AMBIRVALUE: Ambient IR Digital Sample Value
    0x00000,
    //Reg46:RED-AMBREDVALUE: RED-AMBIENT RED DIGITAL SAMPLE VALUE
    0x00000,
    //Reg47:IR-AMBIRVALUE: IR-AMBIENT IR DIGITAL SAMPLE VALUE
    0x00000,
     //Reg48:DIGNOSTICS: DIAGNOSTICS FLAGS REGISTER
    0x00000

Thank you!

Hello Farid Mabrouk,

   Looks like the value you are getting is close to saturation. You can reduce the LED current and gain to come out of saturation and get expected value.

Regards,

Midhun Raveendran