nRF5340 QSPI pins

[Andreas L]

Hi, 

Lookin at this ticket https://devzone.nordicsemi.com/f/nordic-q-a/32090/qspi-pin-mux-on-nrf52840 for the nrf52840 it is said that it is ok to put QSPI on any pins (depending on speed). In the nrf5340 OPS pin assignments chapter it is mentioned that you need to enable special purpose pins for the fastest QSPI mode. 

My question is - at what speed can you use any GPIO for the QSPI with no issues ?  We want to avoid doing via-in-pad to get the QSPI pins routed. 

[Kenneth]

Hi,

I assume this is still work in progress, for instance they need to do gpio concurrency tests with the radio to identify pins that may need special care. Currently in the OPS I can find:

7.1.26 QSPI - Quad serial peripheral interface
6–96 MHz configurable clock frequency

9.1.1 aQFN94 pin assignments

AK8 P0.14 IO1 Digital I/O IO1 for QSPI General purpose I/O Dedicated pin for Quad SPI
AK10 P0.15 IO2 Digital I/O IO2 for QSPI General purpose I/O Dedicated pin for Quad SPI
AK12 P0.17 SCK Digital I/O SCK for QSPI General purpose I/O Dedicated pin for Quad SPI
AK14 P0.18 CSN Digital I/O CSN for QSPI General purpose I/O Dedicated pin for Quad SPI
AL5 P0.13 IO0 Digital I/O IO0 for QSPI General purpose I/O Dedicated pin for Quad SPI
AL9 P0.16 IO3 Digital I/O IO3 for QSPI General purpose I/O Dedicated pin for Quad SPI

So using pins AL5, AL9, AK8, AK10, AK12 and AK14 for sure is the preferred for now.

Best regards,
Kenneth