SOYO SY-5SSM User's Manual & Technical Reference page 32

Hardware Setup SY-5SSM & SY-5SSM/5 V1.1
Step 10. Other Connections
1. Serial Port COM 2
In addition to the onboard serial connector COM1 located at the rear
panel, your Motherboard comes with a second serial port COM2
equipped with a flat cable and external connector.
The Motherboard package includes one serial port flat cable with a
9-pin connector.
Plug the 9-pin end of the flat cable into the COM2 serial connector
on the Motherboard, as shown in the figure below, then fix the
external 9-pin connector to the rear panel of the computer case.
Then plug your serial device cable directly into this 9-pin male
connector located at the back of your computer.
9-pin male external
serial connector
COM 2
9-pin serial
flat cable
ATX
Power
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