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Applies to: C51 C Compiler


Information in this article applies to:


When simulating programs for the Infineon C509 and similar devices, the watchdog timer is activated and cannot be disabled. The "watchdog timer start flag" is activated and resets the simulated microcontroller.


The watchdog timer is enabled by default on many Infineon devices. The uVision simulator behaves the same way as the real chip and enables the watchdog timer when simulating your program.

Infineon devices have a pin called PE/SWD with an internal pull-up. When the pin is high, the watchdog is automatically started at CPU reset. This input pin is simulated in uVision by the value of the PE_SWD VTREG. By default, the value is set to 1 to simulate the on-chip pullup. When this VTREG is low at CPU reset, the Watchdog is disabled.


To disable the watchdog timer, you must:

  1. Create a debugger INI file that contains the following commands:
    PE_SWD = 0  /* Disable Watchdog with pin PE_SWD */
    reset       /* perform CPU reset: uses value at PE_SWD */
    g, main     /* execute program til main */
  2. Under Options for Target - Debug - Use Simulator, disable the option "Go till main ()" then enter the filename for the debugger INI file you created.

Article last edited on: 2005-07-09 10:54:51

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