Ametek TM2000 Pro, User Manual

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A-2 | TM 2000 Oxygen Analyzer
Command message Format
Start
Character
node
address
Command
letter
Data Checksum
end
Character
“>”
(ASCII decimal
character 6)
2 hex
ASCII
characters (00‑
FF)
See commands
section for list of
commands
n characters ‑
depends on com‑
mand
2 hex ASCII char‑
acters (sum except
the “>” character
Carriage
return (ASCII
decimal 13)
The command message format is as follows:
Where:
The Start Character is the greater than character (“>”, which is ASCII decimal
character 62 or hexadecimal character 3E).
The Node Address is from 00‑FF, and is represented as two hex ASCII charac‑
ters. Each controller has a unique node address (see the “Communication/Node
Address” section under Setup Key in Chapter 4 for help on specifying node
addresses for controllers).
The maximum number of controllers that can be connected on the
network is 32.
The Command Letter is from ASCII A‑Z (upper case only).
Data is a string of characters whose meaning depends on the command and
where the number of characters returned also depends on the command. Limit is
20 characters.
The Checksum is the sum of all the preceding characters (excluding the > char‑
acter) ‑ modulo 256.
The End Character is a carriage return (equivalent to ASCII decimal character
number 13).
The system disables any checking of the checksum if the checksum
character is equal to ?? (?? is equivalent to 2 ASCII 63 characters).
This makes testing by the programmer easy, but it is strongly recom-
mended that the integrity check is enabled in the final system.
NOTE

NOTE
