topic Re: I.MX8M Plus Enter JTAG Debug in i.MX Processors

I.MX8M Plus Enter JTAG Debug

hjc — Tue, 03 Jan 2023 16:26:05 GMT

When using NXP I.MX8M Plus chip for bare metal development and debugging, and using DStream emulator to connect to the JTAG interface of I.MX8M Plus processor through JTAG, pin JTAG_ MOD has been set to low level, but the development board cannot enter the JATG debugging mode, and the ROM Table of the chip cannot be read using the J-Link emulator. Does the I.MX8M Plus chip disable the JTAG function when it leaves the factory? How can I enable the Cortex-A53 processor in I.MX8M Plus chip to enter the bare metal debugging mode through JTAG? Thank you

Re: I.MX8M Plus Enter JTAG Debug

Bio_TICFSL — Wed, 04 Jan 2023 15:24:16 GMT

Hello,

Yes, JTAG is disable when is leaving the factory, but this is just for rom access you can access to the rest of the code.

Regards

Re: I.MX8M Plus Enter JTAG Debug

hjc — Thu, 05 Jan 2023 08:09:14 GMT

if i no use rom access, how can i do that use the jtag for debug Cortex-a53 bare metal program ?

how can i do that enter jtag debug mode, thank you

Re: I.MX8M Plus Enter JTAG Debug

NXP_USER_05 — Sat, 25 Oct 2025 12:43:00 GMT

Hi,

I have some questions regarding JTAG connectivity and boot options for a custom i.MX8M Plus board.

How do you typically connect your board for debugging — using JTAG or another interface?
- If JTAG is used, do you connect after U-Boot has executed or before boot (at power-on reset)?
In our custom board, USB and SD interfaces are not populated, so we currently have only JTAG available for communication and detection.
- Could you please advise on the correct procedure or configuration to bring up the board only via JTAG ( DSTREAM-ST)?
- Is there any additional configuration needed in the JTAG_MOD / Boot Mode pins for enabling debug access when no boot device is present?