Hongdian H3304 4CH Dual SD MDVR User Manual
Page 18
2 -11
I/O & RS485 & RS232 &5V/12V Interface
No.
Label
Instruction
1
IO_IN1
Collect electrical level, used for turn light, braking,
alarm.etc which involves electrical change.
High level 3V～24V
Low level 0V~2.5V
2
IO_IN2
3
IO_IN3
4
IO_IN4
5
IO_IN5
6
IO_IN6
7
IO_OUT1
Alarm output i n t o electrical level, could connect
external device.
8
IO_OUT2
High level 3.3V
Low level 0V
9
Speed_IN
Connect external speed censor, support sine wave or
square wave input
10
GND
Connect ground
11
PC_TX1
Received Data device receive data (RS232)
12
PC_RX1
Transmitted Data device send data (RS232)
13
GND
Ground
14
PC_TX2
Received Data receive data (RS232)
15
PC_RX2
Transmitted Data device send data (RS232)
16
GND
Ground
17
RS485_B-
485-signal (RS485)
18
RS485_A+
485+ signal (RS485)
19
GND
Ground
20
RS485_B1-
485- signal (RS485)
21
RS485_A1+
485+ signal (RS485)