A-1 host request table – Zigen HX-88 User Manual
Page 35
Matrix Switching System—User Manual
35
A-1 Host Request Table
This RS-232 / RS-485 communication protocol uses five bytes of information as defined below.
BT :
0: Instruction for device ID only.
(Broadcast)
1: Instruction for all devices. (Device ID must be written 0)
※Devices will not response, when receiving the broadcast request.
0 (Reserve) : Reserve, Always 0.
1 (Identifier) : Identifier, Always 1.
Device ID : Device id ranges from 0 to 31.
VAR : 0: Normal length command. (Recommended)
(variable) 1: Variable length command. (Only support the command is Ack
Type A)
If the VAR (variable) is 1, please refer to the table below.
CRC : Send CRC code to follow the last byte.
LB (Length) :
LB value is equal to the total (Index + Value). Not include the CRC byte.
The default maximum length is 128. (If the extended information does
not exist.)
※The default baud rate is 9600, with no parity, 8 data bits and 1 stop bit.
Host
Target + Request + Index + Value + CRC
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Target
BT
0
1
Request
VAR
0
Index
Value
CRC
CRC
Device ID (0 - 31)
Index
Value
Request (0 - 63)
Variable Target + Request + LB + Index1 + Value1 + Index2 + Value2 + ..... + CRC
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Target
BT
0
1
Request
VAR
0
LB
Index 1
Value 1
…
Index n
Value n
CRC
Value n
Index n
Device ID (0 - 31)
Request (0 - 63)
Index 1
Value 1
CRC
Length
……