VX4101A Operational Modes
VX4101A MultiPaq Instrument User Manual 2–7
card. As a query is received, it is assigned the current sequence number. The next
query received will have a sequence number one larger than the last.
NOTE. Note that sequence numbers are global to the card and have no direct
correlation with the instrument number.
The sequence number defaults to zero on power-on. To set the sequence number
to a desired value, use the following command:
SYSTem:RQUeue:SNUMber[SET]<sequence number>
After the instrument receives this command, the next received query will be
assigned the <sequence number> specified in the command. Each subsequent
sequence number will increment by 1 each time a query is received.
The query SYSTem:RQUeue:SNUMber[:SET]? can be used to determine what
the next sequence number will be. Since the response to this query will contain a
sequence number itself (assuming numerical tags are enabled), the response to
this query will be the sequence number which will be used by the next query
received.
For example, if the message is the sixth message in the queue and the Counter
identification number is 3, the response for the example above would be:
3:6,1.00000000000000E+07
The sequence number formats enable you to identify the instruments according
to your own unique requirements. Using the longer ASCII format allows you to
type commands into a talker/listener to get easily readable feedback about the
source of the current response. The more terse numerical format is easier to parse
in automated test software.
When there is no data in the response queue, the following response will be
generated in numeric mode:
0:Ć1,EMPTY
When the response queue has overflowed, the following response will be
generated in numeric mode:
0:Ć2,OVERFLOW