Manual

Distribution Amplifier (DA)—User Manual
53
Appendix D RS-232 Communication Protocol
This AV Matrix RS-232 communication protocol uses fixed length with 5 bytes of
information as define below. The default baud rate is 9600 bps, no parity, 8 data bit and
1 stop bit. Command timeout is 300 milliseconds, and byte to byte timeout is 30 ms.
Use the RS-232 connecting cable to connect the computer serial port to the RS-232
communication port of this device. The computer can control the device via RS-232.
Aside from using the front panel keys for operation, you are also permitted to use the
RS-232 connection port for remote operation.
D-1 Host Request
A standard command is 5 bytes:
Device + Request + Index + Value + CRC
Byte 1: Device Byte (DB)
Byte 2: Request Byte (RB)
Byte 3: Index Byte (IB)
Byte 4: Value Byte (VB)
Byte 5: CRC Byte (CB)
) Host must send CRC code to follow the last byte.
D-1.1 Device Byte
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
DB
BT 0 1 Device ID (0 - 31)
BT: Broadcast Command Flag.
0 - Instruction for Device ID only
1 - Instruction for all devices. (Device ID must be written 0)
) Devices will not response, when receiving the broadcast command.
0: Reserve, Always 0.
1: Identifier, Always 1.
Device ID: Device id ranges from 0 to 31. (Please refer to device’s user manual)