Boonton 4541, Инструкция по эксплуатации

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Boonton 4540 Series RF Power Meter
Remote Operation
5-5
5.5 Basic Measurement Information
The easiest way to obtain a reading is by use of the MEASure command. This command initiates one complete measurement
sequence which includes a default configuration. Examples are:
MEAS1:POWER? To return the average power of channel 1, or
MEAS1:VOLTAGE? To return the average voltage of channel 1.
For finer control over the measurement, individual configuration and function commands should be used.
Readings are
obtained using the FETCh[ ]? command for current data or the READ[ ]? command for fresh data. These commands may
return multiple results if an array is read.
Readings are in fundamental units as set by the
CALCulate[1|2]:UNIT command. Each reading is preceded by a condition
code, which has the following meaning:
-1 Measurement is STOPPED. Value returned is not updated.
0 Error return. Measurement is not valid.
1 Normal return. No error.
2 An Under-range condition exists.
3 An Over-range condition exists.
With the
INITiate:CONTinuous OFF condition, a single measurement cycle is started by use of the
INITiate[:IMMEDIATE] command, where bracketed commands are optional. Multiple triggered measurement cycles are
enabled by INITiate:CONTinuous ON and a TRIGger:SOURce selection. If TRIGger:MODE is set to FREERUN, a free
running measurement process is started. Otherwise, a measurement cycle begins with each valid trigger condition.
5.5.1 Service Request
Service requests provide a means to signal the host that a particular event or group of events have occurred in the instrument.
Service requests are controlled by the Status Byte Register and the Service Request Enable Register. The Service Request
Enable Register is a bit mask that determines which summary bits of the Status Byte Register can cause a request for service
to be sent to the Controller. The summary bits of the Status Byte are the MAV, or Message Available bit, and three bits from
event driven registers. The first of these is the Standard Event Status Register. The bits of this register are set and latched by
specific events within the instrument and cleared when the register is read. The remaining two registers are the Operation
Status Register and the Questionable Status Register. These two registers are similar to the Standard Event Status Register
but have the additional capability to detect changes in the individual bits of the associated register’s condition register. The
bits are not only selected by a mask register, but a change in a selected bit, either a high to low, low to high or either
transition, can be specified by transition mask registers.
The Status Byte is read by the
*STB? command. The bit enable mask is set by the *SRE command and read by the *SRE?
query. The Standard Event Status Register is read by the *ESR? Command and the bit enable mask is set by the *ESE
command or read by the *ESE? Command.
The Operation Status Register is read by the STATus:OPERation:CONDition? command. The transition masks are set by
the STATus:OPERation:NTransition and STATus:OPERation:PTransition commands. The bit enable mask is set by the
STATus:OPERation:ENABle command and read by the STATus:OPERation:ENABle? query. The Operation Event
Register is read by the STATus:OPERation:EVENt? query.
The Questionable Event Status Register has the same structure as the Operation Status Register. Refer to the command
descriptions that follow for detailed information.