MCBX51: STRANGE PROBLEMS WITH APPLICATION SOFTWARE

Information in this article applies to:

• µVision All Versions
• MCBx51 Evaluation Board

QUESTION

I'm testing my application program using the Monitor on the MCBx51 Board. However, I have strange problems with my software. The problems did not exist with the Eval Version that I have used before. What can be wrong?

CONNECTION TO TARGET SYSTEM LOST!

What is going wrong?

ANSWER

It seems that you have enabled the option Stop Program Execution with Serial Interrupt (under µVision - Project - Options for Target - Debug - Keil Monitor Driver Settings - Stop Program Execution with Serial Interrupt). When you enable the serial interrupt option, the monitor will automatically write the serial interrupt vector. Therefore you must reserve the interrupt vector in your program to avoid that code or data will be overwritten.

Add the following to your application to reserve the serial interrupt of the on-chip 8051 UART.

char code reserve [3] _at_ 0x23;         /* Space for on-chip UART serial interrupt */

Add the following to your application to reserve the serial interrupt of the external UART.

char code reserve [3] _at_ 0x3;          /* Space for EXT0 interrupt */

If you have not enabled Stop Program Execution with Serial Interrupt, you do not have to reserve this memory.

MORE INFORMATION

• Getting Started User's Guide, Chapter 11. Using Monitor-51, Using Stop Program Execution with Serial Interrupt

SEE ALSO

• MCBX51: PROBLEMS WITH MON51 AND TIMER 2
• MON51: STRANGE BEHAVIOR OF PROGRAM CODE

Last Reviewed: Monday, May 10, 2004