SDIO change order of data pins

[Mira H. (deactivated upon user]

Posted on May 08, 2017 at 16:18

Hi everyone,

Is it possible to change the order of the data pins by software? I messed up and connected D0 with D3 and D1 with D2 and so on, between an STM32F765 and a WLAN Chip WL1807 (TI).

I'm using STM32CubeMX.

Best regards,

Mira

#sdio #stm32f765

[S.Ma]

Posted on May 08, 2017 at 16:49

Probably not, otherwise the Alternate function table in the datasheet would be meaningless.

Seems this will be handy:

http://sg.element14.com/roadrunner/rrp-a-105/wire-0-15mm-assorted-pk-4/dp/5017233?ost=5017233&categoryIdBox=&selectedCategoryId=&searchView=table&iscrfnonsku=false

 

[Tesla DeLorean]

Posted on May 08, 2017 at 17:03

Other than modifying the in-memory buffers, no.

[Mira H. (deactivated upon user]

Posted on May 08, 2017 at 18:01

Thanks for answering so quickly.

I guess, scraping away the microstrip lines and rewiring won't work, since the four data lines need to be of the same length.

[S.Ma]

Posted on May 08, 2017 at 19:55

These are not differential lines. at 300ps per inch, it's doable 

[Tesla DeLorean]

Posted on May 08, 2017 at 22:32

I've wire-wrapped without incident, reasonably consistent lengths are sufficient.

[Mira H. (deactivated upon user]

Posted on May 09, 2017 at 09:28

It's just that the data sheet says 'SDIO traces must be (...) as short as possible. In addition, every trace length must be the same as the others'.

But you're right, as long as it doesn't deviate by a couple of inches, it should work alright.Thanks again!

[S.Ma]

Posted on May 10, 2017 at 20:12

The ideal situation vs the good enough one.