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TLV320ADC3101EVM-K: PPS process flow do not work after upgrading the sampling frequency

Part Number: TLV320ADC3101EVM-K

Dear  expert,

the PPS process flow do not work after upgrading the sampling frequency from 24K to 22.05K, it seems like the dsp register do not write successfully, the time waveform is not correct as expected in the process flow, for example, there is an absolute block in the right output, but the timewave in the right channel do not turn up in the Audacity display, could you pls help to identify what is the reason?

the PPS can work properly before upgrading, I don't know what else should I take care of?

Remark: the downloading result is successful after clicking the "Build"--->"downloading and run" , and no error comes out.  and also the ADC3101 CS can also recognise the EVM board

is there any specialized USB driving package for the EVM?

the PPS code is as below:

;IADC = %%prop(miniDSP_A_Cycles);
reg[47][95]=0x00
reg[47][96]=0x00
reg[47][97]=0x00

reg[0][1]=0x01
reg[0][61] = 0x00 ; reg(0)(0x3d => 61) ADC ADC prog mode
reg[0][4] = 0x03 ; PLL_CLKIN = MCLK, CODEC_CLKIN=PLL_CLK
reg[0][5] = 0x91 ; P=1, R=1
reg[0][6] = 0x08 ; J=8, settings are for fs = 44.1khz
reg[0][18] = 0x84 ; reg(0)(0x12 => 18) ADC Powerup NADC = 4, mkmkmk add an additional divide by 2 vs 3254 since only 512 instructions available
reg[0][19] = 0x84 ; ADC Powerup MADC = 4
reg[0][27] = 0x00 ; reg(0)(0x1b => 27) Mode = i2s & wordlength = 16
reg[0][20] = 128 ; reg(0)(0x14 => 20) ADC AOSR = 128
reg[0][83] = 0x0 ; adc vol control = 0db
reg[0][84] = 0x0 ; adc vol control = 0db
reg[0][22] = 4 ; Decimation Ratio = 4
reg[0][21] = %%eval(%%prop(miniDSP_A_Cycles)/2) ; IADC
PROGRAM_MINIDSP_A
reg[1][52] = 0xfc ; reg(1)(0x34 => 52) ADC IN1_L is selected for left P
;reg[1][54] = 0x3c ; reg(1)(0x36 => 54) ADC CM1 is selected for left M
reg[1][55] = 0xfc ; reg(1)(0x37 => 55) ADC IN1_R is selected for right P
;reg[1][57] = 0x3c ; reg(1)(0x39 => 57) ADC CM1 is selected for right M
reg[1][59] = 0x00 ; reg(1)(0x3b => 59) ADC unmute left mic PGA
reg[1][60] = 0x00 ; reg(1)(0x3c => 60) ADC unmute right mic PGA

reg[0][81] = 0xc2 ; reg(0)(0x51 => 81) ADC Powerup ADC left and right channels (soft-stepping disable)
reg[0][82] = 0x00 ; reg(0)(0x52 => 82) ADC Unmute ADC left and right channels

  • Hi,

    The firmware for the USB-MODEVM motherboard is configured for 44.1kHz by default. To change the clocks that are provided to the device from the TAS1020b you need to follow the steps outlined here: 

    After that you will need to make sure your clock configuration of the ADC is appropriate for the sample rate you intend to run at.

    Best,

    Zak

  • Dear Zak,

    thanks for the reply.

    the clocks do not change actually,  I just change the sampling frequency by adjusting the P,R,J ,D coefficient.  the clocks provided by the board is still 11.2896M,

    from the ADC3101 CS software display (see the attached pic), you can see that the board sampling frequency is changed successfully to 22.05KHz.

  • Hi,

    So you are operating the device in master mode? You may need to update the configuration in the PPS framework then as PPS will initialize the device with values different then what you are programming in the CS GUI.

    Best,

    Zak

  • Dear Zak,

    Yes,  the MCLK is provided by the USB board

    but still, the PPS can not work properly after downloading the configuration, it seems like the PPS can not update the related regisgter value. is there anything else should I take care or should I change the pin connection of the hardware? (I am using the onboard microphone as the input)

    the time waveform in the Audacity is not correct.  the right channel is not turn up . I have already change the sapling frequency into the default 44.1KHz.

  • Dear Zak,

    Yes,  the MCLK is provided by the USB board

    but still, the PPS can not work properly after downloading the configuration, it seems like the PPS can not update the related regisgter value. is there anything else should I take care or should I change the pin connection of the hardware? (I am using the onboard microphone as the input)

    the time waveform in the Audacity is not correct.  the right channel is not turn up . I have already change the sapling frequency into the default 44.1KHz.

  • finally I find the rootcause, the input source of the Audacity should be selected as the USB-EVM