Initial pin status inquiry of RT1021

[stanley-kylee]

Hello.
I am using the MIMXRT1020-EVK.

I read the 'i.MX RT1020 Crossover Processors for Consumer Products, Rev. 3.1, 03/2022' manual.
I'm looking at the Default Settings for each pin on page 83, and I have a question here.
(I did a Mass Erase in MCUXpresso. So there is no firmware program running.)

1. The initial state of 'PIMC_STBY_REQ' is Output/Pull-Up/100K. But the voltage on this pin is 0V. Why is 3.3V not output?

2. Does 'Keeper' mean the same as floating?

3. In connector J18 of 'EVK', 0V is output from No.1 (GPIO_AD_B1_10) and No.4 (GPIO_AD_B1_13), and 3.3V is output from No.2 (GPIO_AD_B1_11) and No.3 (GPIO_AD_B1_12).
GPIO_AD_B1_11 and GPIO_AD_B1_12 are connected to 'USB_OTG1_ID' and 'USB_OTG1_OC' respectively. Is it for this reason?

Thanks in advance for your reply.

[CarlosGarabito]

hi @stanley-kylee  all this information you can find in our Reference Manual (https://www.nxp.com/docs/en/data-sheet/IMXRT1020CEC.pdf), in the chapter 12 you find GPIO. which talk about pull-up, pull-down and keeper logic "When Keeper is enabled, the pull-up and pull-down are disabled, and the output value of the pad depends on the Keeper. The output keeper is powered by OVDD. When the core VDD is powered down or the first inverter is tri-stated, the pad’s state can be kept. Keeper and Pull can’t be enabled together."

Best Regards

Carlos

[stanley-kylee]

Hello @CarlosGarabito !!
Thank you for your reply.

I understand the description of Keeper.

1. "When the core VDD is powered down or the first inverter is tri-stated, the pad’s state can be kept."
  → Does that mean that a certain pin is powered off (VDD is powered down) in high state, and when rebooted, that pin boots to high state?

2. Re-ask the content of question 1 in the main text.
  → I attached a 10K or 100K Pull-Up external resistor to the PMIC_STBY_REQ pin.
But when I measure the voltage, it measures 0V. I don't understand.
Serial Flash connected to RT1021 has no firmware. (It's been Mass Erase) The reason I'm doing these tests is because I have a job to use in the production process.

Thanks in advance for your reply.
Have a nice day always.

[CarlosGarabito]

Ok, check your boot sequence, it looks that something is missing

or the boot sequence

it could be good if you add the firmware to check that everything is ok