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Syntax Description
LogicAnalyze Displays statistics about the current signal recording.
LogicAnalyze variable_name Start signal recording for the specified variable or VTREG name.
LogicAnalyze KILL * Remove a variables from signal recording.

You may use the Logic Analyzer in µVision3 to record the time and value of variable changes. As your program runs, the results of the signal recording display in the Logic Analyzer window.

The following commands are available for working with the Logic Analyzer.


The LA command, when entered with no additional arguments, displays statistics about each recorded variable. The number of recorded changes is listed.

LA variable_name

The LA command, when followed by the name of a variable or VTREG in your target program, creates a signal that is recorded. You may record up to 256 variables or VTREG's.  Signal recording is only possible for scalar variables or VTREGs of the type char, unsigned char, int, unsigned int, long, or unsigned long. 


  • The µVision3 simulation does not provide exact timing on some communication peripheral pins. Read/write signals for UART, I²C, CAN and are not toggled, instead VTREGs are used to represent the communication stream.  Therefore it is impossible to review changes of such communication signals.

The LA KILL * command removes the recording of all variables from the Logic Analyzer.

>LA Tone.y1            /* Start recording for y1 member of struct Tone */
>LA CC1_OUT            /* Start recording for CC1_OUT which is a PWM output signal */
>LA AN0                /* Start recording for VTREG AN0 which represents a A/D input */
>LA ADC_DAT            /* Start recording for ADC_DAT that represents the A/D output register */
>LA Signal             /* Start recording for the variable Signal */

/* After execution of the user program ... */

>LA                    /* display statistics for the signal recording */
  1: ''Tone.y1' nRec=211
  2: ''CC1_OUT' nRec=810
  3: ''AN0' nRec=5644
  4: ''ADC_DAT' nRec=400
  5: ''Signal' nRec=0

>LA KILL *             /* Remove all variables from signal recording */
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