User manual

Planning Your Application Program
Chapter 6
6-4 Apply with ASCII Command for ADAM-5000/TCP
System For users do not familiar to Modbus protocol, Advantech
offers a func- tion library as a protocol translator, integrating ASCII
command into Modbus/TCP structure. Therefore, users familiar to ASCII
command can access ADAM-5000/TCP easily. Before explaining the
structure of ASCII command packed with Modbus/TCP format. Let’s
see how to use an ASCII command and how many commands are
available for your pro- gram.
TCP Format Modbus Format ASCII Command
Figure 6-3: ASCII Command Structure in ADAM-5000/TCP
6-4-1 Sytax of ASCII
Command Syntax:
[delimiter character][address][slot] [channel][command][data][checksum]
[carriage return] Every command begins with a delimiter character.
There are four valid characters:
$ and @
The delimiter character is followed by a two-character address (hex-deci-
mal) that specifies the target system. The two characters following the
address specified the module slot and channel. Depending on the
command, an optional data segment may follow the command string.
An optional two- character checksum may also be ap- pended to the
command string. Every command is terminated with a carriage return
(cr).
Note: All commands should be issued in UPPERCASE characters only!
The command set is divided into the following four categories:
· System Command Set
· Analog Input Command Set
· Analog Output Modules Command Set
· Digital I/O Modules Command Set
ADAM-5000/TCP User’s Manual
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