Advantech SOM-4450 CPU System On Module SOM-4450 ETX - Manual (Page 17)

Chapter 2 Connectors and Pin Assignments 1 1
2.2 Pin Assignments for X1, X2, X3, X4
connectors
Please refer to SOM-ETX Design and Specification Guide, Chapter 2
2.3 Safety precautions
Warning! Always completely disconnect the power cord from
your board whenever you are working on it. Do not
make connections while the power is on, because
sensitive electronic components can be damaged by
a sudden rush of power.
Caution! Always ground yourself to remove any static charge
before touching the board. Modern electronic devices
are very sensitive to static electric charges. Use a
grounding wrist strap at all times. Place all electronic
components on a static-dissipative surface or in a
static-shielded bag when they are not in the chassis.