The Program and Debug Interface (PDI) is a Microchip proprietary interface for external programming and on-chip debugging of a device. PDI Physical is a 2-pin interface providing a bidirectional half-duplex synchronous communication with the target device.
When designing an application PCB, which includes an Microchip AVR with the PDI interface, the pinout shown in the figure below should be used. One of the 6-pin adapters provided with the Power Debugger kit can then be used to connect the Power Debugger probe to the application PCB.
Figure 1. PDI Header Pinout
