Tabor Electronics 5251, Руководство пользователя

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4
Remote Programming Reference
IEEE-STD-488.2 Common Commands and Queries
4-85
IEEE-STD-488.2
Common
Commands and
Queries
Since most instruments and devices in an ATE system use similar
commands that perform similar functions, the IEEE-STD-488.2
document has specified a common set of commands and queries
that all compatible devices must use. This avoids situations where
devices from various manufacturers use different sets of commands
to enable functions and report status. The IEEE-STD-488.2 treats
common commands and queries as device dependent commands.
For example, *TRG is sent over the bus to trigger the instrument.
Some common commands and queries are optional, but most of
them are mandatory.
The following is a complete listing of all common-commands and
queries, which are used by the 5251
*CLS - Clear the Status Byte summary register and all event registers.
*ESE <enable_value> - Enable bits in the Standard Event enable
register. The selected bits are then reported to the status byte.
*IDN? - Query the generator’s identity. The returned data is organized
into four fields, separated by commas. The generator responds with its
manufacturer and model number in the first two fields, and may also
report its serial number and options in fields three and four. If the latter
information is not available, the device must return an ASCII 0 for each.
For example, Model 5251 response to *IDN? is:
Tabor,5251,0,1.0
*OPC - Set the "operation complete" bit (bit 0) in the Standard Event
register after the previous commands have been executed.
*RST - Resets the generator to its default state. Default values are
listed in Table 4-1.
*TRG - Triggers the generator from the remote interface. This
command effects the generator if it is first placed in the Trigger or Burst
mode of operation and the trigger source is set to "BUS".
Error Messages In general, whenever the 5251 receives an invalid SCPI command,
it automatically generates an error. Errors are stored in a special
error queue and may be retrieved from this buffer one at a time.
Errors are retrieved in first-in-first-out (FIFO) order. The first error
returned is the first error that was stored. When you have read all
errors from the queue, the generator responds with a 0,"No error"
message.
If more than 30 errors have occurred, the last error stored in the
queue is replaced with -350, “Queue Overflow”. No additional errors
are stored until you remove errors from the queue. If no errors have
occurred when you read the error queue, the generator responds
with 0,"No error".
The error queue is cleared when power has been shut off or after a
*CLS command has been executed. The *RST command does not