FLEXIO -SPI -external flash device id read Issue

[bharat07]

Hi guys, I am working on the s32k144 ev board and I am trying to read the external flash (Winbond) device id using flexio - spi port. For that I am sending 0x9F as instruction, I am getting some data from the MISO line but I am unable to read it. I am using SOSC 8Mhz as  clock for flexspi, using baud rate of 1Mhz. When I probed it using a logic analyzer it is showing an error as a settings mismatch I have attached pic please refer. Could you please help me regarding where I am doing wrong? 

[bharat07]

I don't think Hardware connection is the issue because when I use Pin from the GPIO section in the Pin MUX settings and connect it to CS Pin of flash I am able to read the device id properly (please refer to the image below) but if I used  Pin from FLEXIO section and connected to CS of flash I am getting this error and unable to read it. Attached measuring setup for your reference.Measuring setup

When used pin from GPIO section as CS pin

[danielmartynek]

Does the external flash expects the CS to be asserted between frames?

The expected SPI protocol must be described in the datasheet of the flash.

BR, Daniel

[danielmartynek]

Hello @bharat07,

The MOSI signal and the clock are good.

There must be some HW issues with the MISO line or the the external flash.

Can you measure the signal on the pin of the external flash?

Regards,

Daniel