6.
Troubleshooting
If you are having problems with MPLAB PICkit 4 In-Circuit Debugger operation, start here.
6.1
Some Questions to Answer First
1.
Which device are you working with?
Often an upgrade to a newer version of MPLAB X IDE is required to support newer devices.
2.
Are you using a Microchip demo board or one of your own design? And, have you followed the
guidelines for resistors/capacitors for communications connections?
.
3.
Have you powered the target?
The debugger cannot power the target if greater than 50 mA. For applications needing more than 50 mA, use
an external power supply to power the target board.
4.
Are you using a USB hub in your setup? Is it powered?
If you continue to have problems, try using the debugger without the hub (plugged directly into the computer).
5.
Are you using the USB cable shipped with the debugger?
Other USB cables may be of poor quality, too
long or do not support USB Communication.
6.2
Top Reasons Why You Can't Debug
1.
Oscillator not working
. Check your Configuration bits setting for the oscillator. If you are using an external
oscillator, try using an internal oscillator. If you are using an internal PLL, make sure your PLL settings are
correct.
2.
No power to the target board
. Check the power cable connection.
3.
Incorrect V
DD
voltage
. The V
DD
voltage is outside the specifications for this device. See the device
programming specification for details.
4.
Physical disconnect
. The debugger has become physically disconnected from the computer and/or the target
board. Check the communications cables’ connections.
5.
Communications lost
. Debugger to PC communication has somehow been interrupted. Reconnect to the
debugger in MPLAB X IDE or MPLAB IPE.
6.
Device not seated
. The device is not properly seated on the target board. If the debugger is properly
connected and the target board is powered, but the device is absent or not plugged in completely, you may
receive the message:
Target Device ID (0x0) does not match expected Device ID (0x%x)
, where
%x
is the expected device ID.
7.
Device is code-protected
. Check your Configuration bits settings for code protection.
8.
No device debug circuitry
. The production device may not have debugging capabilities. Use a debug header
instead. (See the
“Processor Extension Pak and Debug Header Specification”
(DS50001292) in
.)
9.
Application code corrupted
. The target application has become corrupted or contains errors. Try rebuilding
and reprogramming the target application. Then initiate a Power-On-Reset of the target.
10.
Incorrect programming pins
. The PGC/PGD pin pairs are not correctly programmed in your Configuration
bits (for devices with multiple PGC/PGD pin pairs).
11.
Additional setup required
. Other configuration settings are interfering with debugging. Any configuration
setting that would prevent the target from executing code will also prevent the debugger from putting the code
into Debug mode.
12.
Incorrect brown-out voltage
. Brown-out Detect voltage is greater than the operating voltage V
DD
. This
means the device is in Reset and cannot be debugged.
13.
Incorrect connections
for the correct communication connections.
14.
Invalid request
. The debugger cannot always perform the action requested. For example, the debugger
cannot set a breakpoint if the target application is currently running.
Troubleshooting
©
2020 Microchip Technology Inc.
User Guide
DS50002751D-page 32
