spi interface in Beagle Bone Black

[Shiva]

Dear All,

I am trying to send and receive data from Beagle bone to my FPGA board. 

HW connections are made properly. 

When I boot the BBB, I could see /dev/spidev*.* devices. 

Start the FPGA in slave mode and BBB in master mode. 

Configured the BBB as following: 

config-pin P9.17 spi_cs
config-pin P9.18 spi
config-pin P9.21 spi
config-pin P9.22 spi_sclk

Then I tried to send some data from BBB. But Data always returns as 255. when I check clock it is always low and all other lines are always high. 

Could any one let me know if anything else, we need to add for SPI0 to work? 

The linux version I am using is:

Linux beaglebone 4.19.94-ti-r42 #1buster SMP PREEMPT Tue Mar 31 19:38:29 UTC 2020 armv7l GNU/Linux

regards

ksr

[Anil Kumar Pugalia]

Have you configured their pin muxing in the dtb? By default they are not configured as SPI.

Regards
Anil

Passion: https://sysplay.in (Playing with Systems)

Shiva wrote on 20/09/23 10:19 pm:

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[Shiva Reddy]

Hi Anil,

For this version of OS, they are already enabled. 

The reason I would say this because, I see spi devices in /dev/ . 

So, we still need to still do anything in dtb?

To view this discussion on the web visit https://groups.google.com/d/msgid/inside_linux/7e9d85e4-8128-30d2-1dea-116531d45960%40sarika-pugs.com.

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Thanks & Regards
- Shiva

[Anil Kumar Pugalia]

It would be best if you could confirm on the SPI lines, if signals are coming as expected.

Regards
Anil

Passion: https://sysplay.in (Playing with Systems)

Shiva Reddy wrote on 21/09/23 11:22 pm:

To view this discussion on the web visit https://groups.google.com/d/msgid/inside_linux/CAGsq-yuGaUYQbJELc4cyKxjoMN1JEZU_uyKrE7Suu_YnzyR%3Ddw%40mail.gmail.com.