Agilent Technologies D, 66311B, 66309B, 66111A manual Measurement Commands, FORMat, 104

8 – Language Dictionary

Measurement Commands

Measurement commands consist of format, measure, and sense commands.

Format commands specify the data formatting of all array queries. You can specify the data type, type length, and byte order.

Measure commands measure the output voltage or current. Measurements are performed by digitizing the instantaneous output voltage or current for a specified number of samples, storing the results in a buffer, and calculating the measured result. Two types of measurement commands are available: MEASure and FETCh. MEASure commands trigger the acquisition of new data before returning the reading. Measurement overflows return a reading of 9.91E+37. FETCh commands return a reading computed from previously acquired data. If you take a voltage measurement, you can fetch only voltage data.

♦Use MEASure when the measurement does not need to be synchronized with any other event.

♦Use FETCh when it is important that the measurement be synchronized with either a trigger or with a particular part of the output waveform.

Sense commands control the current measurement range, the bandwidth detector of the dc source, and the data acquisition sequence.

FORMat

This command selects the data type and the type length for all array queries. Supported types are ASCII and REAL. When ASCII is selected, the response format for these queries is NR3 Numeric Response Data. This format is selected at *RST. The only valid argument for <length> is 0, which means that the dc source selects the number of significant digits to be returned.

When REAL is selected, the array response format is Definite Length Arbitrary Block Response Data. The data within the Arbitrary Block is coded as IEEE single precision floating point, with 4 bytes per value. The second argument to the FORMat:DATA command specifies the number of bits in the returned data. Only the value 32 is permitted in dc source instruments. The byte order within a single value is determined by the FORMat:BORDer command. Definite Length Arbitrary Block Response Data format begins with a header that describes the number of data bytes in the response. The header begins with a pound sign, followed by a single non-zero digit that defines the number of digits in the block length, followed by the digits contained in the block.

For example: The response to the query "MEAS:ARR:CURR:[DC]? 1" which returns 45 numeric values

would be as follows: ’#’ ’3’ ’1’ ’8’ ’0’ <byte1> <byte2> ... <byte180> <newline>

Command Syntax	FORMat[:DATA] <type> [,length]
Parameters	ASCii REAL
*RST Value	ASCii
Examples	FORM REAL
Query Syntax	FORMat?
Returned Parameters	<CRD>
Related Commands	FORM:BORD MEAS:ARR:CURR:DC? MEAS:ARR:VOLT:DC?

104