i.MXRT117x - Can FlexSPI1 and FlexSPI2 both be run at full clock speed of 133MHz?

[KMurp]

We are trying to run 2 QSPI NOR Flash devices, one on FlexSPI1 as XIP and the second on FlexSPI2 for data logging.

Pins for FlexSPI1 are GPIO_SD_B2_06 through 11 with GPIO_SD_B2_05 left floating for DQS.

Pins for FlexSPI2 are GPIO_EMC_B2_10 through 16, with GPIO_EMC_B2_12 left floating for DQS.

Everything works, however, we can't get FlexSPI2 to run at full clock speed of 133MHz.  If this is possible, we haven't figured out how to do it.  We can only run FlexSPI2 at half clock frequency.  The DQS pin on GPIO_EMC_B2_12 doesn't seem to matter if it's configured as the DQS or not.

Is it possible to run FlexSPI2 at full clock frequency, and how should we configure that?

Thanks,

Kevin

[jingpan]

Hi @KMurp ,

Yes, flexspi2 can run at 133Mhz. Have you configureflexspi2 DQS to kFLEXSPI_ReadSampleClkLoopbackFromDqsPad?

Regards,

Jing

[KMurp]

Thank you for the quick reply!

Yes, we tried that and could not get full clock speed.  Any other suggestions would be appreciated.

Kevin

[jingpan]

Hi @KMurp ,

Did you follow the flexspi hardware design rule in RT1170 hardware design guide?

Regards,

Jing

[KMurp]

Yes.  I went back to the Hardware Design Guide and verified that our design is consistent with the rules in the latest document.

Thanks,

Kevin