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Applies to: MON51 Target Monitor


Information in this article applies to:


I have started to use Monitor-51. Every time I start the uVision debugger, I get the message:

Monitor Error 26: Cannot Write Interrupt-Vector

What is the reason for this error message?


This error message is generated when the Monitor is not able to write the serial interrupt vector into the memory. Typically, this indicates that the Monitor is not installed at address 0x0000 and that the serial interrupt vector (typically at code address 0x0023) cannot be overwritten.

This error message indicates that the Monitor is incorrectly configured or that your hardware has problems with the von-Neumann wired CODE memory in address region 0x0000.

To avoid this problem, disable the option Stop Program execution with serial Interrupt under Project -> Options for Target -> Debug -> Monitor Settings. When this option is disabled, the monitor does not try to intercept the serial interrupt. However, you will not be able to stop a running program without a reset.

To correct this problem, you must determine why the monitor is unable to write to code space starting at 0x0000.

Article last edited on: 2004-04-24 12:30:58

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