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.
Use the pinout shown in the figure below when designing an application PCB with an AVR
with the PDI interface included.Figure 2-2. PDI Header Pinout
Direct Connection to a Standard 6-pin 100-mil PDI Header
Use the included 100-mil 6-pin flat cable to connect directly to a board supporting the
PDI header type. Note the pin-1 marking on the cable, and ensure to line it up with the
pin-1 marking on the AVR Programming Adapter.
Note: The RESET pin is used for clocking the PDI. It is important
to bypass or avoid any circuitry that can distort the clock signal during
programming or debugging, such as capacitors and external reset sources.
