Huawei AR500 Series Hardware Description page 668

Huawei
AR500&AR510&AR531&AR550&1500&AR2500
Industrial Switch Routers
Hardware Description
l
Issue 10 (2019-03-06)
Table 6-24 Levels on DI lines
Switch
Open
Closed
DI
3.3V
DI/DO interface
DI
Use of the DO lines:
– Connection of any of DO lines 0, 1, and 2: Connect the positive pole of an LED to
the 3.3 V power supply line a current-limiting resistor, and connect the negative
pole of the LED to a DO line.
– Connection of any of DO lines 3, 4, and 5: Connect the positive pole of an LED to a
DO line and connect the negative pole to the GND line.
Determine the levels on the DO lines according to
Table 6-25 Levels on DO lines
LED
On
Off
Copyright © Huawei Technologies Co., Ltd.
DI Lines 0, 1, 2
High level
Low power
3.3V
DIDO0，DIDO1，DIDO2
DIDO3，DIDO4，DIDO5
Switch
GND
Table
DO Lines 0, 1, 2
Low power
High level
6 Cables
DI Lines 3, 4, 5
High level
Low power
Switch
6-25.
DO Lines 3, 4, 5
High level
Low power
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