AD9164 SPI multibyte data transfer issue


i am using AD9164 in NCO only mode and i am trying to use multibyte data transfer of AD9164, before that, everything works well in SPI single byte access. also AD9164 is functioning well after single byte SPI mode initialization.

my controller send out the multibyte SPI access timing as below picture, one access was splitted into 2 pictures just easy for reading. the blue channel is CS, green is SDIO and pink is SCK.

in this pictures i am trying to write 2 bytes data 0x03, 0x35 at reg 0x118, the ADDRINC is 0, (reg 0x0=0). i suppose that after this write, 0x118=0x03, 0x117=0x35.

but the write operation totally not work. the 0x118 and 0x117 was not update at all when i read reg out in single byte read mode. also the  NCO output is not change after FTW update 0x113 toggling. again, everything works well if in single byte access. if i switch to single byte write, the 0x118 and 0x117 could be updated.

I also tried to enable the multibyte transfer(0x1[7] = 0), or enable CS stalling(0x1[6] = 1), but still not working. also tried different spi frequency, different wirte length, different address. never successful in multibyte mode...

could you give me some clue on this issue? thanks

[edited by: at 2:44 PM (GMT 0) on 22 Jul 2019]

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