Could not stop ARM device!

Hello Alessandro,

Thank you for using the Keil tools for ARM.

Sorry to hear about the "Could not stop ARM device" For context, from the : ULINK2 User Guide, "Error Messages" section:

"The debugger tries to stop the target. This attempt can be made after initializing the connection, or while resetting the target, or through a stop/step command while debugging. In some cases, the target's debug block not functioning properly raises this error."

I saw you tried to lower the JTAG Speed, as mentioned in KB article MCB2103: ULINK - CANNOT STOP ARM DEVICE!

Other things you could try:

• Check your ULINK2 settings. See:
  • KB article: ULINK: JTAG COMMUNICATION FAILURE
  • KB article: ULINK: HOW TO SET THE ULINK VCC JUMPER
• Try erasing your chip by doing a hard reset followed by a Flash -> Erase. Details of this method can be found in this thread:
• Forum: JTAG communication problem: device not found
• Use the 3rd-party tool "Flash Magic" and erase - via In System Programming (ISP) - your device via a com port. See MCB2100 User's Guide: Downloading with Flash Magic
• Try an example project from  Keil's Legacy support for Arm7, Arm9 & Cortex-R devices  (downloadable from the MDK v4 Legacy Support page). Once you have downloaded it, try this LPC2129 example:
  • C:\Keil_v5\ARM\Boards\Keil\MCB2100\Blinky\blinky.uvproj
• If that works well, then check your application code to see if they changed the disabled JTAG pins. See:
  • KB Article: ULINK: PHILIPS LPC2000 ARM DEVICE DOES NOT REACT
  • KB article: MCB2140: HOW TO RE-ENABLE JTAG ON LPC21XX DEVICES
• Try the suggestions in this forum post
  • Forum: Could not stop ARM device

Hopefully, you will be able to connect to your device. Good Luck.

Hello Alessandro,

Thank you for using the Keil tools for ARM.

Sorry to hear about the "Could not stop ARM device" For context, from the : ULINK2 User Guide, "Error Messages" section:

"The debugger tries to stop the target. This attempt can be made after initializing the connection, or while resetting the target, or through a stop/step command while debugging. In some cases, the target's debug block not functioning properly raises this error."

I saw you tried to lower the JTAG Speed, as mentioned in KB article MCB2103: ULINK - CANNOT STOP ARM DEVICE!

Other things you could try:

• Check your ULINK2 settings. See:
  • KB article: ULINK: JTAG COMMUNICATION FAILURE
  • KB article: ULINK: HOW TO SET THE ULINK VCC JUMPER
• Try erasing your chip by doing a hard reset followed by a Flash -> Erase. Details of this method can be found in this thread:
• Forum: JTAG communication problem: device not found
• Use the 3rd-party tool "Flash Magic" and erase - via In System Programming (ISP) - your device via a com port. See MCB2100 User's Guide: Downloading with Flash Magic
• Try an example project from  Keil's Legacy support for Arm7, Arm9 & Cortex-R devices  (downloadable from the MDK v4 Legacy Support page). Once you have downloaded it, try this LPC2129 example:
  • C:\Keil_v5\ARM\Boards\Keil\MCB2100\Blinky\blinky.uvproj
• If that works well, then check your application code to see if they changed the disabled JTAG pins. See:
  • KB Article: ULINK: PHILIPS LPC2000 ARM DEVICE DOES NOT REACT
  • KB article: MCB2140: HOW TO RE-ENABLE JTAG ON LPC21XX DEVICES
• Try the suggestions in this forum post
  • Forum: Could not stop ARM device

Hopefully, you will be able to connect to your device. Good Luck.