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8
Make COM Cable
8.1
Make RS232 COM Cable
Please refer to the following figure to make RS323 cable.
When use the network keyboard to control the analog matrix, RS232 Com adopts the straight
mode:
2-2, 3-3, 5-5.
Straight through connection mode is shown as in Figure 8-1.
Figure 8-1
When use the keyboard to control other device, RS232 Com adopts the crossover connection
mode:
2-3, 3-2, 5-5.
Crossover connection mode is shown as in Figure 8-2.
Figure 8-2
8.2
Make RS485 COM Cable
Note
RS232 port can only connect to one DVR. If you want to control several DVRs at the same
time, please use RS485 mode.
RS485 BUS can connect to thirty-two 485->232 switcher boxes, one 485->232 switcher box
can connect to 8 DVRs.
You can refer to Figure 8-3 if you are connecting the keyboard with the switcher box.
RS485 Port of Keyboard RS485 Switch Box Port
（
Green alarm socket
）
（
6-pin crystal
）
