DRA821U: SPI - TCS time adjustment

Part Number: DRA821U

Hi.

My customer has this question regarding the tcs time.

Please see the below request:

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We measure the tcs time of SPI to be about 4us for SPI_CS and SPI_CLK signals (as below image1), but we expect the tcs time to be lower than 111.6ns.

According to the specification, we can adjust the tcs time (as below image2). We change tcs time to 0 (as below image3).

However, after the actual measurement, the tcs time interval between SPI_CS and SPI_CLK is still very large (about 4us).
We anticipate that the time of tcs should be much less than 4us because we are using a 5M SPI transfer rate.
How do we adjust the tcs time to be as small as the time defined by the spec (Image2)?

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Any comments?

BR Rio

  • Rio,

    Can you please attach the images?

  • Hi 

    We measure the tcs time of SPI to be about 4us for SPI_CS and SPI_CLK signals (as below image1), but we expect the tcs time to be lower than 111.6ns. According to the specification, we can adjust the tcs time (as below image2). We change tcs time to 0 (as below image3). However, after the actual measurement, the tcs time interval between SPI_CS and SPI_CLK is still very large (about 4us).
    We anticipate that the time of tcs should be much less than 4us because we are using a 5M SPI transfer rate.
    How do we adjust the tcs time to be as small as the time defined by the spec (Image2)?

    BR

    JAY

  • Hi 

    We measure the tcs time of SPI to be about 4us for SPI_CS and SPI_CLK signals (as below image1), but we expect the tcs time to be lower than 111.6ns. According to the specification, we can adjust the tcs time (as below image2). We change tcs time to 0 (as below image3). However, after the actual measurement, the tcs time interval between SPI_CS and SPI_CLK is still very large (about 4us).
    We anticipate that the time of tcs should be much less than 4us because we are using a 5M SPI transfer rate.
    How do we adjust the tcs time to be as small as the time defined by the spec (Image2)?

    BR

    JAY

  • Hi JAY

    As per the specs, this field is available only in master mode and with automatic CS generation, ie in multiple channel mode. Otherwise this big will not be used. Can you please check and confirm that you are using correct mode? 

    Regards,

    Brijesh