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SPI streaming mode

Question asked by yeaten on Apr 5, 2017
Latest reply on Apr 6, 2017 by gverma

Is there a planning for implementing SPI streaming mode for AD9371? While I was reviewing the API I noticed that it is missing. I completed common.c for AD9528 but as you guess it is just several tens of bytes for AD9528. The main problem is arm image. It takes to much time to load ~100 kB data because 66% of bits is waste of data.

 

Eval board does not work with 40 Mbps SPI, I think because of voltage translater and SDO sw. Read data comes 1 bit shifted(0xFF->0x7F, 0x90->0x48 etc.). I achieved to make it work with 25Mbps. It takes ~100kB x 8bit x 3 x 40ns = ~96 ms just for arm image.

 

Also, I am working with microblaze processor and memory is noteworthy thing for me. In my opinion, API has some redundant buffers for spi. For example,

  • unsigned char txbuf[SPIARRAYSIZE] in common.c 1024B
  • uint16_t addrArray[MYK_SPIWRITEARRAY_BUFFERSIZE]
    uint8_t dataArray[MYK_SPIWRITEARRAY_BUFFERSIZE] 3 times in mykonos.c

At least last 3 of them can be merge into one. Of course if there is streaming mode, none of them will be necessary.

 

Thank you

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