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Error Messages

This list identifies errors that might occur when using ULINKplus. If you are experiencing difficulties, contact our support group.

ULINKplus

No ULINKplus firmware found
Communication is lost or ULINKplus is not working. Unplug ULINKplus from the USB port and plug it back in.
Firmware Download Failed
ULINKplus firmware cannot be downloaded. Use the firmware download tool available at C:\Keil_v5\ARM\ULINK to update the firmware manually.
No ULINKplus device found
No ULINKplus detected. ULINKplus is not connected to the USB port, or the USB driver is not installed properly, or ULINKplus is not working properly. Reconnect or connect ULINKplus to the USB port of the PC.
No ULINKplus is selected
No ULINKplus adapter has been selected for debugging. Occurs when more ULINKplus adapters have been detected, but none has been selected. Select one ULINKplus from the Serial No drop-down list in the Target Driver Setup dialog. Use Options for Target - Debug - Settings.
ULINKplus Communication Timeout
Communication is lost or corrupted. Unplug ULINKplus from the USB port and plug it back in.
USB Communication Failure
USB communication is lost or corrupted. Unplug ULINKplus from the USB port and plug it back in.
Parameter Error
Internal driver error. Please report it to our support group.

RDDI-DAP errors

RDDI-DAP errors indicate that the serial wire debug connection is corrupted. Typically, they are indicated by the following messages:

RDDI-DAP Error

Serial Wire RDDI-DAP Error

RDDI-DAP errors can be caused by:

  • an unpowered target (check the target's power supply)
  • a missing physical connection to the target (check your 10-pin Arm Cortex cable)
  • a maximum JTAG/SW clock that is set too high (lower the Max Clock frequency in the Target Driver Setup - Debug dialog)
  • a device in deep-sleep mode

JTAG errors

JTAG errors indicate that the JTAG communication is corrupted or that the device chain is not set up correctly. They are indicated by the following messages:

JTAG Error

JTAG Chain Error

JTAG errors can be caused by:

  • an unpowered target (check the target's power supply)
  • a missing physical connection to the target (check your 10-pin Arm Cortex cable)
  • a maximum JTAG/SW clock that is set too high (lower the Max Clock frequency in the Target Driver Setup - Debug dialog)
  • a device in deep-sleep mode
  • devices on that JTAG chain not meeting the requirements, or an improperly configured chain when chaining multiple targets.

Problems entering Debug mode

If not configured properly, you might face issues to enter the debug mode or to download an image to the target's Flash memory. This is indicated by the following messages:

Cannot access target

Cannot access memory

Flash Memory Time Out

Could not load file

These errors can be caused by:

  • an unpowered target (check the target's power supply)
  • a missing physical connection to the target (check your 10-pin Arm Cortex cable)
  • a device in deep-sleep mode
  • connecting to the wrong device. If you have multiple ULINKplus debug adapters in your system (connected to different target devices), check that you are accessing the right one. Select the ULINKplus -JTAG/SW Adapter in the Target Driver Setup - Debug dialog. Attention: selecting "Any" will select the first device ULINKplus in the list.

Other Debug Errors

Cannot enter Debug Mode
Debug Interface on the target cannot be accessed. The target debug interface is not working properly. Mainly caused by target problems: debug block not powered or clocked properly. Avoid Deep-Sleep modes while debugging. Lower the Max Clock frequency in the Target Driver Setup - Debug dialog.
Could not stop Cortex-M device
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. This Knowledgebase Article details some other possible conditions which could cause this error.
Device could not be powered up
Debug block on the device could not be powered. Debug block on the target is not working properly. Mainly caused by target problems: debug block not powered and clocked properly.
Memory Mismatch
Memory mismatch detected while downloading the code to target. Appears when the option Verify Code Download is enabled and when a debugging session is started. Then the code in the target is compared against the load image. The message is raised when the target's Flash was not programmed with the code being debugged. Download the program to Flash.
Could not stop ARM device
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.

Breakpoints and watchpoints

It was not possible to disable all breakpoints
Occurs when breakpoints cannot be disabled while the target is running. Stop the target to perform this operation.
Operation not possible while target device is executing
This operation is not possible or failed while the target is running. Occurs in situations where breakpoints cannot be enabled or disabled while the target is running.
This target device does not support all the defined breakpoints
Too many breakpoints have been defined. Reduce the number of breakpoints.
This target device does not support all the defined watchpoints
Too many watchpoints have been defined. Reduce the number of watchpoints.
This target device does not support conditional breakpoints
Remove all conditional breakpoints.
This target device supports only the following watchpoints:
    size = 2^n; n = 0..15
    start must be 2^n aligned
    with optional value match
Change the watchpoint definition.
It was not possible to kill all breakpoints
Usually occurs when breakpoints cannot be killed while the target is running. Stop the target to perform this operation.

Related Knowledgebase Articles

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