µVISION DEBUGGER: WATCHDOG RESET SIMULATING SILABS DEVICE

Information in this article applies to:

• C51 Compiler Version 7.0 or higher
• µVision Version 2.4 or higher

QUESTION

I am using the Keil µVision Debugger/Simulator for developing code on SiLabs (formerly Cygnal) devices. Since I am using a new software version, I get messages like:

**************************************
*** Watchdog Timer Reset Occurred. ***
**************************************

This also causes a restart of the application software. What is wrong now?

ANSWER

The Silicon Laboratories devices start after reset with the WatchDog timer enabled. When the watchdog is not refreshed the devices reset. This is reflected in the µVision Simulator. The old version that you used before did not cover full device simulation for SiLabs devices and therefore there was no watchdog reset.

For the SiLabs 80C51F3xx devices you may disable the watchdog using the following statement at the beginning of the main function. Other devices may require a slightly different instructions.

void main (void) {
  PCA0MD &= ~0x40;              // disable watchdog
    :
    :

MORE INFORMATION

• SiLabs Devices Users Guides

Last Reviewed: Tuesday, June 07, 2005