High to NANDF_RB3 causes lockup in iMX.51

[MichaelMcCarty]

Hello Everyone,

   Hopefully i'll get a response to this question ? 

   We are using the pad NANDF_RB3 for a gpio signal and this signal is sometimes high when the board starts. It is high from external circuitry connected to the board. As long as the signal is low for about a second while the imx51 boots there is no issue. 

   why would having this pin high cause the whole module to lock up ? I've read in the datasheet and note that this pin is used in a daisychain could this be causing the issue ? 

   thanks for your time, and any response is welcome!

[MichaelMcCarty]

Thanks ! This was a tricky one, next time we will check the errata. Or maybe the first time next time ;)

best wishes!

[mdc]

Assume when you say lock up you mean the board won't boot from NAND. All 4 R/B lines need to be stable and high when coming out of reset when booting from NAND.

Have a look here:

http://imxcommunity.org/forum/topics/imx51-nfc-nandf-rb-b