Top Reasons Why You Can't Debug
- 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.
- No power on the target board - Check the power cable connection.
- Incorrect VDD voltage - The VDD voltage is outside the specifications for this device. See the device programming specification for details.
- Physical disconnect - The debugger has become physically disconnected from the computer and/or the target board. Check the communication cables’ connections.
- Communications lost - Debugger to PC communication has somehow been interrupted. Reconnect to the debugger in MPLAB® X IDE.
- 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 get the message: "Target Device ID (0x0) does not match expected Device ID (0x%x)," where %x is the expected device ID.
- Device is code-protected - Check your configuration bits settings for code protection.
- No device debug circuitry - You are trying to debug a production device that does not have debugging capabilities. Use a debug header instead. (See the “Processor Extension Pak and Debug Header Specification DS50001292” in Recommended Reading.)
- 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 (POR) of the target.
- Incorrect programming pins - You do not have the correct PGC/PGD pin pairs programmed in your configuration bits (for devices with multiple PGC/PGD pin pairs).
- 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 emulator from putting the code into debug mode.
- Incorrect brown-out voltage - Brown-out Detect voltage is greater than the operating voltage VDD. This means the device is on Reset and cannot be debugged.
- Incorrect connections - For more details, see Operations.
- MPLAB ICD 4 Page
- MPLAB ICD 4 Getting Started
- ICD 4 Block Diagram
- ICD 4 Operation
- ICD 4 Debugger to Target Communication
- ICD 4 Debugging
- Quick Debug/Program Reference
- Setting up the Target Board
- Starting And Stopping Debugging
- Breakpoints And Stopwatch
- The Five Questions To Answer First
- Other Things To Consider