8MPLUSLPD4-PEVK

[takahashi1]

I am planning to develop RTOS-based firmware on the M7 with the i.MX8M plus.

I'll use A53 with Linux.

So I'm using the evaluation kit "8MPLUSLPD4-PEVK" that I have, building a sample project with MCUXpresso for VSCode, and trying to test debugging with Segger's j-Link.

I was able to generate the target elf and bin without any problems up until the build stage, but when I tried to debug, I couldn't connect to the target evaluation kit with j-Link.

The evaluation kit is SD booted, and u-boot is started with the debug UART, but Linux has not yet started.

Since I can't connect from VS Code in this state, I tried to connect with Segger's j-Link commander, but I couldn't connect.

I'd like to know if there are any settings required to debug the M7 via JTAG.

Below is the log from j-Link commander

SEGGER J-Link Commander V8.46 (Compiled Jun 26 2025 07:49:03)
DLL version V8.46, compiled Jun 26 2025 07:48:12

Connecting to J-Link via USB...O.K.
Firmware: J-Link V11 compiled Apr 1 2025 10:02:30
Hardware version: V11.00
J-Link uptime (since boot): 0d 00h 01m 58s
S/N: 51020038
License(s): GDB
USB speed mode: High speed (480 MBit/s)
VTref=1.704V

Type "connect" to establish a target connection, '?' for help
J-Link>connect
Please specify device / core. <Default>: MIMX8ML8_M7
Type '?' for selection dialog
Device>
Please specify target interface:
J) JTAG (Default)
S) SWD
T) cJTAG
TIF>
Device position in JTAG chain (IRPre,DRPre) <Default>: -1,-1 => Auto-detect
JTAGConf>
Specify target interface speed [kHz]. <Default>: 4000 kHz
Speed>
Device "MIMX8ML8_M7" selected.

Connecting to target via JTAG
ConfigTargetSettings() start
ConfigTargetSettings() end - Took 1.91ms
InitTarget() start
InitTarget() end - Took 54.9ms
TotalIRLen = ?, IRPrint = 0x..000000000000000000000000
Failed to identify target. Resetting via Reset pin and trying again.
ConfigTargetSettings() start
ConfigTargetSettings() end - Took 22us
InitTarget() start
InitTarget() end - Took 52.6ms
TotalIRLen = ?, IRPrint = 0x..000000000000000000000000
Error occurred: Could not connect to the target device.
For troubleshooting steps visit: https://kb.segger.com/J-Link_Troubleshooting
J-Link>

[pengyong_zhang]

Hi @takahashi1 

i have tested the helloword demo on my i.mx 8MP EVK board, there is no error occured. Make sure your board is boot normal in uboot, and your J-link connect right. Did you try the helloword demo?

B.R

[pengyong_zhang]

HI @takahashi1 

Please share your this picture, check if your PC can find the J-Link device.

[takahashi1]

The j-Link itself is connected.

[takahashi1]

I followed the instructions in this document but was unable to connect.

Below is the terminal output from muuxpresso.

Connecting to J-Link...
J-Link is connected.
Device "MIMX8ML8_M7" selected.
Firmware: J-Link V11 compiled Apr 1 2025 10:02:30
Hardware: V11.00
S/N: 51020038
Feature(s): GDB
Checking target voltage...
Target voltage: 1.71 V
Listening on TCP/IP port 2330
Connecting to target...
ConfigTargetSettings() start
ConfigTargetSettings() end - Took 78us
InitTarget() start
InitTarget() end - Took 54.1ms
TotalIRLen = ?, IRPrint = 0x..000000000000000000000000
Failed to identify target. Resetting via Reset pin and trying again.
ConfigTargetSettings() start
ConfigTargetSettings() end - Took 27us
InitTarget() start
InitTarget() end - Took 55.0ms
TotalIRLen = ?, IRPrint = 0x..000000000000000000000000
ERROR: Could not connect to target.
Target connection failed. GDBServer will be closed...Restoring target state and closing J-Link connection...
Shutting down...
Could not connect to target.
Please check power, connection and settings.[2025-07-02T07:22:26.760Z] SERVER CONSOLE DEBUG: GDB server connection closed.
GDB server connection closed. Terminal will be reused, waiting for next session to start...

[pengyong_zhang]

Hi @takahashi1 

please refer the attachment file.

B.R

[takahashi1]

I have sent a reply to myself so I will reply again.

I followed the instructions in this document but was unable to connect.

Below is the terminal output from muuxpresso.

Connecting to J-Link...
J-Link is connected.
Device "MIMX8ML8_M7" selected.
Firmware: J-Link V11 compiled Apr 1 2025 10:02:30
Hardware: V11.00
S/N: 51020038
Feature(s): GDB
Checking target voltage...
Target voltage: 1.71 V
Listening on TCP/IP port 2330
Connecting to target...
ConfigTargetSettings() start
ConfigTargetSettings() end - Took 78us
InitTarget() start
InitTarget() end - Took 54.1ms
TotalIRLen = ?, IRPrint = 0x..000000000000000000000000
Failed to identify target. Resetting via Reset pin and trying again.
ConfigTargetSettings() start
ConfigTargetSettings() end - Took 27us
InitTarget() start
InitTarget() end - Took 55.0ms
TotalIRLen = ?, IRPrint = 0x..000000000000000000000000
ERROR: Could not connect to target.
Target connection failed. GDBServer will be closed...Restoring target state and closing J-Link connection...
Shutting down...
Could not connect to target.
Please check power, connection and settings.[2025-07-02T07:22:26.760Z] SERVER CONSOLE DEBUG: GDB server connection closed.
GDB server connection closed. Terminal will be reused, waiting for next session to start...