4.2.3 Crystal

The PIC18F57Q43 Curiosity Nano Board has a 32.768 kHz crystal footprint made for standard 3.2 mm by 1.5 mm surface mount crystals with two terminals.

The crystal footprint is not connected to the PIC18F57Q43 by default, as the GPIOs are routed out to the edge connector. Some hardware modifications are required to use the crystal. The two I/O lines routed to the edge connector must be disconnected to reduce the chance of contention to the crystal and to remove excessive capacitance on the lines. This can be done by cutting the two straps on the bottom side of the board, marked RC0 and RC1, as shown in the figure below. Next, solder on a solder blob on each of the circular solder points next to the crystal on the top side of the board, as shown in the figure below.