aWire is a single-pin interface for programming and debugging of low-pin-count AVR 32-bit devices using the RESET pin. All features of the OCD system available through the JTAG interface can also be accessed using aWire.
When designing an application PCB which includes an AVR with the aWire interface, the pinout shown in Figure 1 should be used. While future aWire capable tools will support this pinout, the Atmel JTAGICE mkII requires that the 10-pin "squid" cable is used to map to this pinout.
Figure 1. aWire Header
Pinout
