QT5 Xplained Pro implements one Xplained Pro Standard Extension Header (see also section Xplained Pro Standard Extension Header) marked with EXT1 in silkscreen. This header make it possible to connect the board to an Xplained Pro MCU board with an MCU featuring a PTC module. The pinout definition for the extension header can be seen in the table below.
| Pin on EXT | Function | Description |
|---|---|---|
| 1 | ID | Communication line to ID chip |
| 2 | GND | Ground |
| 3 | Y0 | Y-line 0: Connected to Slider |
| 4 | Y1 | Y-line 1: Connected to Buttons |
| 5 | Not Connected | |
| 6 | Not Connected | |
| 7 | X0 | X-line 0: Connected to Slider and Buttons |
| 8 | X1 | X-line 1: Connected to Slider |
| 9 | X2 | X-line 2: Connected to Slider and Buttons |
| 10 | X3 | X-line 3: Connected to Slider |
| 11 | I2C SDA | Connected to LED driver IC |
| 12 | I2C SCL | Connected to LED driver IC |
| 13 | Not Connected | |
| 14 | Not Connected | |
| 15 | Not Connected | |
| 16 | Not Connected | |
| 17 | Not Connected | |
| 18 | Not Connected | |
| 19 | GND | Ground |
| 20 | VCC | Target supply voltage |