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AT4610/AT4710 User’s Guide
11.1.3
Command Structure
The SCPI commands are tree structured three levels deep. The highest level commands are
called the subsystem commands in this manual. So the lower level commands are legal only
when the subsystem commands have been selected.
A colon (
:
) is used to separate the higher level commands and the lower level commands.
Semicolon (;) A semicolon does not change the current path but separates two commands in
the same message.
Figure 11-1 Command Tree Example
Example
ROOT:CCC:DDD ppp
ROOT
Subsystem Command
CCC
Level 2
DDD
Level 3
ppp
Parameter
11.2
Header and Parameters
A command tree consists of header and parameters, it uses a space
(
ASCII: 20H
)
to separate in
the middle.
Example
AAA:BBB 1.234
Header
[Parameter]
11.2.1
Header
Headers can be of the long form or the short form. The long form allows easier understanding of
the program code and the short form allows more efficient use of the computer.
11.2.2
Parameter
Single command word, no parameter.
Example: AAA:BBB
Parameter can be character string form, the abbreviation rules are the same as the rules
for command.
Example: AAA:BBB 1.23
Parameter can be numeric form
<integer>
integer 123, +123, -123
<float>
floating number
1. <Fixfloat>
：
fixed point floating number
：
1.23
, -1.23
ROOT
AAA
BBB
CCC
DDD
EEE
