User Manual
A9000
AC Power Source
78
│
www.deltaww.com
6.2.4 Basic Definition for Command
Construction of DME-A902ABT SERIES remote control command is based on tree system,
every command must have a full path so instrument can receive it.
Tree structure use
”:”
as node. Command or data at left side of node is in higher level
while at right side is in detail level. More commands are at more left side, more details are
at more right sides.
DME-A902ABS SERIES includes two distinctive types of command. The first one is
command described in IEEE 488.2, it is common commands for GPIB, represented by
”
*
”
at beginning of the command. The second one is instruments self-defined commands. All
commands are not upper/ lower case sensitive.
There are some special symbols in commands
:
Colon (:)
:
Colon represents node for tree system, use colon to downstream to different
parameter until complete command constructed. For example: VOLT:AC?
Question mark (?)
:
Question mark represents this message is question, instruments
will prepare the answers for sender to read. If sender does not read
after sending questions, instrument will reserve the answer for last
question command.
Example
:
computer send
:
VOLT:AC?
Instrument side
:
150.0
semicolon(;)
:
there are two usages for semicolon,
:
1. First usage
:
back to previous node,
Example
:
VOLT:AC 100;LIM:AC 200
Explanation
:
Th
¬
e above instruction has two commands which are VOLT:AC 100
VOLT:LIM:AC 200, (;) can save one repeated string VOLT and complete
two commands in one instruction, instrument will execute commands in
sequence.
2. 2
nd
usage
:
first input semicolon then colon, represents command branches from
beginning,
Example
:
VOLT:AC 100;:FETCh:CURRent:AC?
Explanation
:
The above instruction has two commands which are VOLT:AC 100 and
FETCh:CURRent:AC?. Use (;:) can connect commands more than two.
Space( )
:
Space is used to separate command and number or string after it. Instrument
differentiate command and data by space.
Example
:
VOLT:AC 100