YOKOGAWA TA120E, Руководство пользователя

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8-13
IM 704420-01E
Communication Function
8
<Character String Data>
Unlike the predefined character strings of <Character
data>, <Character string data> is an arbitrary character
string. The character string is enclosed in single
quotation marks ( ' ) or double quotation marks ( " ).
Form Example
<Character string data> 'ABC' "IEEE488.2-1987"
• If the character string contains a double quotation
mark ( " ), it is represented by ( "" ). This rule also
applies to a single quotation mark (
'
).
• A response message is always enclosed in double
quotation marks (
"
).
• Because <Character string data> is an arbitrary
character string, if the last single quotation mark (
'
)
or double quotation mark ( " ) is missing, the
instrument may assume that the remaining program
message units are part of the <Character string
data> and may not detect the error.
8.6.6 Synchronization with the
Controller
This instrument does not support overlap commands,
which allows the execution of the next command to
start before the execution of the previous command is
completed. If multiple sequential commands—the type
of commands supported by this instrument—are sent
consecutively, the execution of the next command is
delayed until the execution of the previous command is
completed.
Synchronization Using Sequential
Commands
Even for sequential commands, synchronization is
sometimes required for non communication-related
reasons such as a trigger occurrence.
For example, if the next program message is sent
when querying the measured data of a single
measurement, “ CALCulation:JITTer? ” is executed
regardless of whether the data acquisition has finished
and may result in a command execution error.
:SSTart;:CALCulation:JITTer?<PMT>
In this case, the following method must be used to
synchronize with the end of the acquisition:
Using the STATus:CONDition? query
The “ STATus:CONDition? ” query is used to query
the contents of the condition register (page 8-39)
You can determine whether or not the measured
data are valid by reading bit 0 of the condition
register. If bit 0 of the condition register is “ 1 ,” the
measured data are valid. If it is “
0
,” measurement
or computation is in progress and the measured
data are invalid.
Example : SSTart<PMT>
STATus:CONDition?<PMT>
(Read the response. If bit 0 is 0, repeat
this command until it becomes 1.)
CALCulation:JITTer?<PMT>
8.6 Program Format