RT500 FlexIO QSPI implementation

[djgj]

Hello All,

We are using the RT555 for our new product and we have designed intending to use the FlexIO as a QSPI master.

Originally we had seen the following 2 app notes, and thought this would be possible:

Using FlexIO to emulate Quad SPI master: https://www.nxp.com/docs/en/application-note/AN14175.pdf

Using FlexIO to emulate communications and timing peripherals: https://www.nxp.com/docs/en/application-note/AN12174.pdf

On closer inspection, the QSPI example is a simplex implementation, and the “Dual SPI” is standard SPI, with a single MISO and MOSI pin, and not dual-SPI where both pins are used as a 2-bit half duplex bidirectional link.

Are you aware if it is possible to generate a full bidirectional QSPI bus using the FlexIO peripheral?  Is there any code available to demonstrate this? 

Thanks for your support.

Regards,

djgj

[Habib_MS]

Hello @djgj,

The only documentation for FlexIO & QSPI is the previously mentioned app note, which only covers a simplex transfer. Half/full-duplex mode are possible, but we do not provide any examples or documentation for them.

On the other hand, this post explains how the FlexIO works which could be helpful.

BR
Habib.