AnsweredAssumed Answered

Boot i.mxrt1051 from alternate QSPI pins

Question asked by Eamonn Heffernan on Jun 3, 2020
Latest reply on Jun 9, 2020 by Eamonn Heffernan

Hi, for pin reasons, I'd like to use the alternate/secondary pins for QSPI, connecting to GPIO_AD_B1_xx instead of the primary GPIO_SD_B1_xx pins. Before I commit to a pcb, I have some questions, and I would appreciate any helpful advice.


1. Will the 1051 reliably boot from the alternate pinset? There is no hint given to the device via BOOT_CFG pins to tell it to use the alternate pinset. Does it just test both pinsets, and use whichever one has a flash attached?


2. Does NXP have a schematic for such a configuration? Or a description of how to connect the QSPI to the 1051? (EVKB, Arch Mix, SOMLab Vision boards all use the primary pinset.) Table 11, Page 15 of MIMXRT105060HDUG.pdf provides a list of pins. Is this what I should use?


3. What should I do with FLEXSPI_A_DQS? Mux it out and let it float?


4. Table 3 of AN12108 gives a list of supported QSPI devices. Is this list valid for the alternate pinset too?


5. Can I flash and debug normally with the alternate pinset? (I'm using a Link2 debugger.)


6. Is there any performance difference between the two pinset choices.


7. Any gotchas that I should be aware of?


Ok, a lot of questions, but I would be very grateful if anyone out there who has used the alternate pinset could help me with these questions. I really don't want to print a pcb and then find it just doesn't work.

Thanks so much