Alcorn Mcbride V+ series, Руководство пользователя

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16-2 Appendix B
– Alcorn McBride Serial Control Protocols
The Basics of Alcorn Control
Alcorn Control protocols use a very basic message structure consisting of
several similar components: source address, target address, command byte, and
data bytes.
Note
This appendix uses the prefix
0x
to indicate a hexadecimal number.
Source and Target Address
The Source and Target addresses are derived from the Show Controller’s “Unit
Address” which is a one byte address from
0x00
–
0x79
. The source address is
the address of the unit where the message originated. The target address is the
address of the unit that should receive and process the message.
Note
The source address of an external device, such as a PC, that is controlling
a Show Controller or group of Show Controllers should be 0xFF .
Command and Data Bytes
A “command opcode” is a term used by programmers to describe a single byte
in a serial message that stands for what is to be done. Alcorn Control messages
can turn on and off Outputs and Flags, start Sequences change Variables, and
even remotely display messages on the LCD Display. Each of these functions
requires a different command.
Some command opcodes require additional “data” bytes that further describe
what is to be done in the Show Controller. These data bytes can take the form of
an Output, Flag, Sequence, Port, or State Variable index; DMX or Analog
values; or a message to display on the LCD or send out a Serial Port. The
following table lists the indices of Show Controller resources:
Resource Index
Output 0x00 – 0x3F
Flag 0x40 – 0x7F
State Variable 0x00 – 0x1F
Serial Port 0x00 – 0x11
Sequence 0x00 – 0xFF
Output or Flag Bank 0x00 – 0x01
Note All resource indices in a Show Controller are zero-based.