Microchip Technology MPLAB ICD 3, Руководство пользователя

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Operation

2012-2014 Microchip Technology Inc. DS50002081B-page 19
2.4.5 Circuits That Will Prevent the Debugger From Functioning
Figure 2-5 shows the active debugger lines with some components that will prevent the
MPLAB ICD 3 In-Circuit Debugger system from functioning.
FIGURE 2-5: IMPROPER CIRCUIT COMPONENTS
In particular, these guidelines must be followed:
• Do not use pull-ups on PGC/PGD – they will disrupt the voltage levels, since
these lines have 4.7 k

pull-down resistors in the debugger.
• Do not use capacitors on PGC/PGD – they will prevent fast transitions on data
and clock lines during programming and debugging communications.
• Do not use capacitors on MCLR – they will prevent fast transitions of V
PP
. A
simple pull-up resistor is generally sufficient.
• Do not use diodes on PGC/PGD – they will prevent bidirectional communication
between the debugger and the target device.
No!
No!
No!
No!
V
PP
/MCLR
PGC
PGD
1
5
4
Interface
Connector