µVision4 User's Guide

Watch Variables

You can watch the contents of variables, structures, and arrays using the Watch Window.

The Watch Window updates at the end of each execution command. Enable View - Periodic Window Update to update the watch window during program execution.

View and Modify On-Chip Peripherals

µVision provides several ways to view and modify on-chip peripherals. Use the following procedures to supply input to I/O pins:

• Using Peripheral Dialog Boxes
• Using VTREG Symbols
• Using User and Signal Functions

Using Peripheral Dialog Boxes

µVision4 provides dialogs for: I/O Ports, Interrupts, Timers, A/D Converter, Serial Ports, and chip-specific peripherals. These dialogs can be opened from the Debug menu. For the MEASURE application you may open I/O Ports:Port2 and A/D Converter. The dialogs show the current status of the peripherals and you may directly change the input values.

Each of these dialogs lists the related peripheral register symbols and shows the current status of the peripherals. To change the inputs, change the values of the Pins or Analog Input Channels.

Using VTREG Symbols

Assign values to VTREG symbols using the Command window. Assignments to VTREGs are done in the same way as to variables or registers. For example:

PORT2=0xDA00 set digital input PORT2 to 0xDA00.
AIN1=3.3 set analog input AIN1 to 3.3 volts.

Using User and Signal Functions

It is possible to combine VTREGs with user-defined signal functions to create complex methods for providing external input to target programs. The Analog Example shows a signal function that provides input to AIN0. The signal function is included in the MEASURE example and can be invoked with the Toolbox button Analog0..3V. The method changes the voltage on the input AIN0 continuously.