3.3.4.1.2 SAM JTAG Pinout (Cortex®-M debug connector)
When designing an application PCB which includes a Microchip SAM with the JTAG interface, it is recommended to use the pinout as shown in the figure below.
| Name | Pin | Description |
|---|---|---|
| TCK | 4 | Test Clock (clock signal from the MPLAB ICD 5 into the target device). |
| TMS | 2 | Test Mode Select (control signal from the MPLAB ICD 5 into the target device). |
| TDI | 8 | Test Data In (data transmitted from the MPLAB ICD 5 into the target device). |
| TDO | 6 | Test Data Out (data transmitted from the target device into the MPLAB ICD 5). |
| nRESET | 10 | Reset (optional). |
| VTG | 1 | Target voltage reference. Not used by MPLAB ICD 5. |
| GND | 3, 5, 9 | Ground. All must be connected to ensure that the MPLAB ICD 5 and the target device share the same ground reference. |
| KEY | 7 | Connected internally to the TRST pin on the AVR connector. Recommended as not connected. |
Tip: Remember to include a
decoupling capacitor between VTG and GND.