What does FLASH_AUTO_PROBE do?

joogoosa — Fri, 13 Feb 2026 16:33:30 GMT

Hello, while configuring BOOT options using BOOT pins, we came across this option to enable FLASH_AUTO_PROBE (i.MX RT1170 Processor Reference Manual, Rev. 4 page 2111).

Can you please elaborate what this feature does and what is it used for?

In addition to that, could it hinder normal boot operation when using HyperFLASH or Octal Flash?

Re: What does FLASH_AUTO_PROBE do?

stephanie_m — Mon, 16 Feb 2026 21:31:58 GMT

Hello,

When the xSPI FLASH Auto Probe feature is enabled, the following is the logic how this feature works with other fuse combinations:

Flash Type - If Flash type is 0, the "xSPI FLASH Auto Probe Type" takes effect for the Flash type selection. If Flash Type is greater than 1, the "Flash Type" fuse is used for Flash type selection, ROM will issue specific command to probe the presence of Serial NOR FLASH.
xSPI FLASH Frequency - This field is used for specifying the Flash working frequency.

Would you help check if this the following information is helpful?

This information is available on the latest version of the Reference Manual of the RT1170 page 285.

Regards,

i.MX RT Crossover MCUsのトピックWhat does FLASH_AUTO_PROBE do?

What does FLASH_AUTO_PROBE do?

Re: What does FLASH_AUTO_PROBE do?