User manual
37 Chapter 4 
4.4.1 COM port Pin 9 power output setting (JP3)
Pin 9 on COM port can act as power output, and the settings available are 
shown as below:
4.4.2 COM port Pin 9 power output value setting (JP4)
Table 4.8: COM port Pin 9 power output setting (JP3)
External power output disable 
(Default)
External power output enable
Note: 1. Pins 1, 3, 5 are for COM1
2. Pins 2, 4, 6 are for COM2
3. Pins 7, 9, 11 are for COM3
4. Pins 8, 10, 12 for COM4 
5. 
The external power output value is determined by 
JP4, as described in the next section.
Table 4.9: COM port Pin 9 power output value setting (JP4)
Default (5V) Option (12V)
97
8
531
6421012
11
97
8
531
6421012
11
1
23
1
23










