The 12 edge connections closest to the USB connector on Curiosity Nano kits have a standardized pinout. The program/debug pins have different functions depending on the target programming interface as shown in the table and figure below.
| Debugger Signal | ICSPTM Target | Description |
|---|---|---|
| ID | - | ID line for extensions |
| CDC TX | UART RX | USB CDC TX line |
| CDC RX | UART TX | USB CDC RX line |
| DBG0 | ICSPDAT | Debug data line |
| DBG1 | ICSPCLK | Debug clock line/DGI GPIO |
| DBG2 | GPIO0 | DGI GPIO |
| DBG3 | MCLR | Reset line |
| NC | - | No connect |
| VBUS | - | VBUS voltage for external use |
| VOFF | - | Voltage Off input |
| VTG | - | Target voltage |
| GND | - | Common ground |
Figure 1. Curiosity Nano Standard
Pinout