The measurement process restarts when there is again room to store readings in the output buffer.

Measurement Format Readings in the output buffer have the following characteristics:

•Readings sent to the output buffer can consist of two different lengths(bytes or characters) in Real ASCII format:

±1.23456E±12 LF or

±1.234567E±12 LF

•Each measurement is terminated with a Line Feed (LF). The HP-IB End-or-Identify (EOI) signal is sent with the last byte transferred. If multiple measurements are returned, the measurements are separated

by commas and EOI is sent only with the last byte. For example:

±1.23456E±12 LF,±1.234567E±12 LF,±1.23456E±12 LF EOI

•The multimeter’s internal memory stores 512 readings maximum.
MEASURE1 Source Code File
Use the MEAS Command to Make a Single Measurement

*RST

Reset the multimeter.

MEAS:VOLT:DC?

Configure dc volts (default settings) and measure

enter statement

retrieve the reading from the multimeter.

Enter reading into computer

Comments • The MEASure command configures the multimeter for the function specified and initiates the measurement. The reading is stored in the output buffer and you must provide the I/O construct to retrieve the reading and enter it into the computer.

MEASURE2 Source Code File
Making Externally Triggered Measurements (multiple triggers/samples)

*RST CONF:VOLT:DC 18 TRIG:SOUR EXT TRIG:COUN 3 SAMP:COUN 10 INIT

FETC?

enter statement

Reset the multimeter.

Configure for dc volts, expected input = 18V. Set trigger source to external.

Set trigger count to 3.

Set sample count to 10 per trigger.

Puts multimeter in wait-for-trigger state. EXTernal triggers occur here to initiate measurements. Measurements are stored in multimeter internal memory.

Transfer measurements from the multimeter internal memory to the output buffer and retrieve them with the computer.

Enter reading into computer.

Comments • You must provide a TTL external trigger signal to the HP E1312A or HP E1412A front panel “Trig” input BNC. Measurements are triggered by low pulses of this signal. Each trigger results in 10 readings.

•The CONFigure command configures the multimeter for the function specified. This CONFigure command specifies a range parameter of 18 (expected input is 18V; the multimeter sets a range to accommodate that input which will be 100V). It does not initiate the measurement.

54 HP E1312A/E1412A Multimeter Application Information

Chapter 2