Advantech PCA-6143P User Manual page 19

You can connect a LED indicator across jumper JP13 to indicate
when the CPU is in Turbo mode. Marks on the circuit board
indicate LED polarity (the lower pin is positive).
The CPU card has its own buzzer. You can also connect to the
external speaker on your computer chassis. Connect leads to
connector JP10 as shown below:
Pin no. Function
1+5 V
DC
2Speaker out
3Speaker out
4Speaker out
In single-board-computer (non-passive-backplane) applications
you will need to connect power directly to the PCA-6143P board
using connector J2. This connector is fully compatible with the
standard PC power supply connector for a 3.5" FDD (or HDD).
See the following table for its pin assignments:
Pin no. Function
1+5 V
DC
2 GND
3 GND
4+12 V
DC
Chapter 3 Connecting peripherals 19