Microchip Technology MPLAB ICE, User Manual

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2001 Microchip Technology Inc. DS51159B-page 17
Quick Start
• This trace buffer can be viewed by selecting Window>Trace Memory.
Up to 32767 instruction cycles can be displayed. The trace memory win-
dow contains the following information for each execution cycle:
- Cycle Number – Cycle’s position relative to the trigger or halting
point. The approximate trigger cycle will be highlighted in blue,
and will be numbered as cycle 0.
- Address (Addr) – Address of the instruction being fetched from
program memory.
- Opcode (Op) – Instruction being fetched.
- Label (Label) – Label (if any) associated with the program mem-
ory address.
- Instruction (Instruction) – Disassembled instruction.
- Source Data Address (SA) – Address or symbol of the source
data, if applicable.
- Source Data Value (SD) – Value of the source data, if applicable.
- Destination Data Address (DA) – Address or symbol of the desti-
nation data, if applicable.
- Destination Data Value (DD) – Value of the destination data, if
applicable.
- External Inputs (Ex) – Value of the external inputs.
- Time Stamp (Cycles or Seconds) – Time stamp value.
• Select Data>Reload to force an upload of whatever data has currently
been collected by the trace buffer. This allows you to see where your
program is executing. This is often useful if your trigger is never
reached.
• The column widths can be adjusted manually by dragging the right col-
umn header border with the mouse. Select Options>Configure to further
customize the trace display.
Usage Problems
If you have difficulty using any of the features of MPLAB ICE, please refer to
the more detailed chapters on features (Chapter 5 or Chapter 6) or consult
the troubleshooting chapter (Chapter 8).
Note: Due to the timing of processor signals, the data information will be
skewed by one cycle. Destination data values are actually skewed
by two cycles, but for display purposes, the trace buffer display
compensates for one of the delayed cycles.
Note: Source and destination data addresses and values are not
available when using processor modules based on the 12-bit
PICmicro
®
core (PIC16C5X and related parts).