Appendix A
API Command Reference
NetScan User’s Manual
A-37
?
- Query
TYPE
System
EXECUTION
Immediate
SYNTAX
?
Query the present configuration or mode of the command preceding the
?
DESCRIPTION
Most commands have a corresponding Query (
?
) command formed by appending a question mark (
?
) to the
command letter. Query commands place their responses into the output queue until the controller retrieves
them. They respond with the present configuration or mode of a previously executed command. When
appropriate, the response from a Query command is in the form of a command string which, if it were executed,
would put the unit into the configuration it was in when the Query was executed.
For instance, the response of the User Terminator Query (
V?X
) command is in the following form:
Vval
where
0
<
val
<
255
. This response is in the form of the Set User Terminator (
V
) command and, if it is sent to the
unit, it would set the User Terminator to the same value that it had when the Query was issued. Query
responses are always fixed-length strings in a pre-defined format.
Any number of Query commands can be combined into one string to create a specialized status command that
responds with only the information of interest for a given application.
Query commands are immediate. Their responses are generated as soon as they are interpreted, before any
other commands, including the Execute (
X
) command.
Note: Even though Query commands generate their responses as soon as they are interpreted, they must still
be followed by an Execute (
X
) command for proper termination. For more information on command
execution, refer to the
X
command reference presented later in this appendix.
EXAMPLE
PRINT#1, “V1 X V? X”
‘ Get the response of current User Terminator
INPUT#1, A$
‘ Retrieve response
PRINT A$
‘ Screen shows
V1
PRINT#1, “V0 X V? X”
‘ Change User Terminator and get response
INPUT#1, A$
‘ Retrieve response
PRINT A$
‘ Screen shows
V0
PRINT#1, “V4 V? X”
‘ Change User Terminator and get response - No
intermediate
X
command
INPUT#1, A$
‘ Retrieve response
PRINT A$
‘ Screen shows
V0
User Terminator. Response is still
V0
because the immediate command
V?
was executed
before the deferred command
V4
PRINT#1, “V? X”
‘ Get User Terminator response
INPUT#1, A$
‘ Retrieve response
PRINT A$
‘ Screen shows new User Terminator
V4
Summary of Contents for OMB-NETSCAN 1500
Page 6: ...iv NetScan User s Manual...
Page 18: ...1 12 Configuring and Starting NetScan NetScan User s Manual Notes...
Page 38: ...3 8 General Information and Specifications NetScan User s Manual Notes...
Page 82: ...4 44 ChartView Software Reference NetScan User s Manual Notes...
Page 118: ...6 20 Calibration NetScan User s Manual...
Page 140: ...A ii NetScan User s Manual...
Page 192: ...API Command Reference Appendix A A 52 NetScan User s Manual Notes...
Page 237: ...Appendix D Registers Data Formats Queries NetScan User s Manual D 13...
Page 244: ...NetScan Program Examples Appendix E E 2 NetScan User s Manual...
Page 248: ...ASCII Code Summary Appendix F F 4 NetScan User s Manual Notes...
Page 250: ...NetScan Error Messages Appendix G G 2 NetScan User s Manual Notes...
Page 252: ...Abbreviations Appendix H H 2 NetScan User s Manual Notes...
Page 254: ...NetScan User s Manual...
