Intan RHD2164 with NRF52840 (SPI) - Double Data Rate Issue

RE: Intan RHD2164 with NRF52840 (SPI) - Double Data Rate Issue

quenmasc — Mon, 26 Apr 2021 19:34:47 GMT

Hi Simon,

Thanks you for your time ! Help me a lot !

Regards

Quentin

RE: Intan RHD2164 with NRF52840 (SPI) - Double Data Rate Issue

Simon — Thu, 22 Apr 2021 12:28:56 GMT

[quote user="quenmasc"]One last question for my understanding, is it the CLK of my SPI that I configure to twice the speed it should be at SLAVE (intan)?[/quote]

From my understanding, the speed on the master (52840) side should be twice the speed required by the slave (intan).

[quote user="quenmasc"]In fact, given the SCK required for the Intan chip, it would be better if I use the SPIM3 which allows 32MHz SCK?[/quote]

Yes, it seems like SPM 0-2 does only support data rates up to 8 Mbps

, so if the speed on the INTAN RHD2164 is 16 Mbps, you need to use SPIM3, to get a speed of 32 Mbps

Best regards,

Simon

RE: Intan RHD2164 with NRF52840 (SPI) - Double Data Rate Issue

quenmasc — Fri, 16 Apr 2021 18:15:57 GMT

Hello Simon,

Thank you for your very enriching answer which allowed me to understand something that I did not know, it is very appreciated!

One last question for my understanding, is it the CLK of my SPI that I configure to twice the speed it should be at SLAVE (intan)? In fact, given the SCK required for the Intan chip, it would be better if I use the SPIM3 which allows 32MHz SCK?

Best Regards,

Quentin

RE: Intan RHD2164 with NRF52840 (SPI) - Double Data Rate Issue

Simon — Fri, 16 Apr 2021 14:07:37 GMT

I don't think you will be able to use QSPI to communicate with the RHD2164, since it uses SPI (with DDR) which is a different protocol. SPI uses two separate data lines for input and output (MISO and MOSI) while the QSPI interface uses four data lines and configures the lines to output/input on the fly. The RHD2164 datasheet says the following:

"Note that this DDR technique is a non-standard mode of SPI communication and will likely require an FPGA to implement."

However, I came over a workaround that might work: https://www.esp8266.com/viewtopic.php?p=66519#p66519

Best regards,

Simon