The Program and Debug Interface (PDI) is a Microchip proprietary two-line interface that was introduced with the AVR XMEGA® microcontroller family. As the name implies, this interface can be used for both In-System Programming and on-chip debugging of devices.
The following figure shows the standard PDI connector supplied with Microchip programmers. Only two pins on the device are required for using this interface; RESET, also called PDI_CLK, and the dedicated PDI_DATA pin. The target’s voltage supply allows power to the device or ensures correct signal levels during programming.
Figure 1. Standard PDI Header
Note: Refer to the respective programmer
user guide for more information about the capabilities and physical interface of
PDI.