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