18 com1, com2 (com1, com2 ) – Acrosser AR-B1551 User Manual
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AR-B1551 User’s Guide
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3.2.18 COM1, COM2 (COM1, COM2 )
COM1 (COM1)
COM2 (COM2)
9
8
7
6
5
4
3
2
1
1
2
3
4
5
6
7
8
9
10
Figure 0-6 COM1 & COM2: RS-232 Connector
CN5 CN6
Signal
CN5 DB6
Signal
1 1
/DCD
6 6
/CTS
2 2
/DSR
7 7
/DTR
3 3
RXD
8 8
/RI
4 4
/RTS
9 9
GND
5 5
TXD
10 --
GND
Table 0-3 RS-232 Connector Pin Assignment
(1) RS-232/RS-485 Select for COM2 (P1 & P3)
The P1&P3 jumper is used to choose between the use of the on-board RS-232 or RS-485 for the COM2.
P3
P1 1
3
2
RS-232
Factory Preset
1
3
2
RS-485
A
C
B
A
C
B
Figure 3-10 P1 & P3: RS-232/RS-485 Select for COM2
(2) RS-485 Terminator Select (JP6)
When there is only one line the setting should be left off, but if you are using multiple blocks on a single line
this should be set to “ON” in order to properly terminate the connection for better transmission of data
OFF
Factory Preset
1
2
1
2
ON
Figure 0-7 JP6: RS-485 Terminator Select