C&B Technology AN120 Series, Communications Manual

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A(V)N(P)120
’
s Protocol Version 1.1
Pelco “D” Protocol Commands
1. Pelco “D” Byte Format
RS485, 2400bps, 1 Start bit, 8 data bits, 1 stop bit, no parity
2. Pelco “D” Message Format
Checksum Data2 Data1 Command2 Command1 Address Sync Byte
BYTE 7 BYTE 6 BYTE 5 BYTE 4 BYTE 3 BYTE 2 BYTE 1
The Sync Byte is always 0xFF.
The Address is the logical address of the receiver/driver device being controlled.
3. Checksum Format
Byte 2 + Byte 3 + Byte 4 + Byte 5+ Byte 6 = Checksum
4. Pelco “D” Standard Command Set
Command 1 and 2 Format
Always 0 Right Left Up Down Zoom
Tele
Zoom
Wide
Focus
Far
Command2
Focus
Near
Iris
Open
Iris
Close
Camera
On/Off
Auto
/Manual
Scan
Reserved Reserved Sense Command1
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7
The reserved bit should be set to 0
5. AN120L (P) Pelco “D” Message
Common Message
Checksum 0x00 0x00 0x80 0x00 Cam ID 0xFF MSG
Focus Far Function
Checksum 0x00 0x00 0x00 0x01 Cam ID 0xFF MSG
Focus Near Function
Checksum 0x00 0x00 0x40 0x00 Cam ID 0xFF MSG
Zoom Wide Function
Checksum 0x00 0x00 0x20 0x00 Cam ID 0xFF MSG
BYTE 7 BYTE 6 BYTE 5 BYTE 4 BYTE 3 BYTE 2 BYTE 1
Zoom Tele Function