µVISION DEBUGGER: Simulating Unsupported Interrupts

Information in this article applies to:

• C51 Version 6.12 and later
• µVision Version 2.12 and later

QUESTION

I'm using a new device that is not completely supported by the µVision Debugger. Specifically, some interrupt vectors are not supported. Is there a way to generate an interrupt in the debugger?

ANSWER

Yes. You can create a script that generates an interrupt on demand. The following debugger function pushes the current program counter onto the stack and sets the program counter to the interrupt vector address you specify:

func void GenerateInterrupt (unsigned char vector) {
  SP++;
  _WBYTE (SP, PC & 0xFF);
  SP++;
  _WBYTE (SP, (PC & 0xFF00) >> 8);
  PC = 0x000000 + vector;
}

For example, to invoke the interrupt at vector address 0x1B, you would call this debugger function as follows:

GenerateInterrupt (0x1B)

Note that you may create a Button on the toolbox or you may attach this function to a breakpoint to automate the interrupt.

Last Reviewed: Thursday, January 21, 2021