Intel iEi Motherboard A300 - Manual (Page 89)

A300 Motherboard
The COM Port Setting jumper configures pin 9 on COM 1, COM 3 or COM 2 as either a
+5V, +12V power source. The CN13 jumper also sets the communication protocol used by
the second serial communications port (COM 3) as RS-232, RS-422 or RS-485. The COM
Port Setting jumper selection options are shown in Table 5-4.
PIN NO. Description PIN NO. Description
Short 1, 3 COM1 Pin9 use +5V Short 2, 4 COM2 Pin9 use +5V
Short 3, 5 COM1 Pin9 use +12V Short 4, 6 COM2 Pin9 use +12V
Short 7, 9 COM3 Pin9 use +5V Short 8, 10 COM3 is RS-232 (default)
Short 9, 11 COM3 Pin9 use +12V Short 10, 12 COM3 is RS-422/485r
Table 5-4: COM Port Setting Jumper Settings
The COM Port Setting jumper location is shown in Figure 5-10 below.
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