4.1.4 Cortex Debug Connector
The Cortex® debug connector is provided to enable external debuggers to be connected to the ATSAMR21G18A. The footprint is made for a 2x5 50mil connector and the pinout is shown in the table below. This header should only be used when the EDBG is disconnected from the target. For more information, see 1.8V Operation.
| Pin on connector | Connected | Function |
|---|---|---|
| 1 | VCC Target | Voltage reference |
| 2 | PA31_SWDIO | Debug data |
| 3 | GND | GND |
| 4 | PA30_SWCLK | Debug clock |
| 5 | GND | GND |
| 6 | NC | - |
| 7 | NC | - |
| 8 | NC | - |
| 9 | GND | GND detect |
| 10 | RESETN | Target reset |