Microchip Technology MPLAB ICE, User Manual

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2001 Microchip Technology Inc. DS51159B-page 125
Advanced Features
6.5.3 Reading the Trace Memory Window
Reading the information in the trace memory window requires knowledge of
PICmicro MCU architecture. PICmicro MCU instructions fetch one instruction
cycle while decoding and executing the previous cycle, (i.e., there is a one
cycle pipeline).
In Example 1 (Figure 6.20):
1. The first cycle, the W register is loaded with the value of 0xFF
2. The next cycle, the value gets written into the W register
Figure 6.20: Trace Memory Window – Example 1
In Example 2 (Figure 6.21):
1. The first cycle, a Decrement File and Skip if Zero is applied to a variable
at location 0x20
2. The next cycle, the value of this variable is decremented from 2 to 1
Figure 6.21: Trace Memory Window – Example 2
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