User`s manual

FETCh?
The FETCh? command retrieves measurements stored in mainframe/
command module memory by the most recent
INITiate command and places them in
the output buffer. This command is most commonly used with
CONFigure.
Subsystem Syntax FETCh?
Comments • Execute INITiate before sending the FETCh? command to place the multimeter in
the wait-for-trigger state. If the multimeter is in the idle state (that is, if
INITiate
has not been executed), FETCh? will generate the “Data corrupt or stale” error.
• Each reading sent to the output buffer consists of 15 bytes (characters) in Real
ASCII format:
±1.234567E±123 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
readings are returned, the readings are separated by commas and EOI is sent only
with the last byte.
• The output buffer capacity is 128 bytes. Therefore, eight readings (15 bytes each)
can be transferred to the output buffer at a time. The mainframe remains "busy"
until you begin removing readings from the output buffer using your computer’s
enter statement.
• This command causes the stored readings in the mainframe RAM to be retrieved
and sent over the HP-IB bus. Readings are not output until all readings are taken
and stored in RAM.
• Readings can be received and placed into RAM at any reading rate up to 13K.
The maximum number of readings is limited by the amount of RAM in the
mainframe (HP E1300, for example). Each reading is four bytes long.
• Related Commands: CONFigure, INITiate, READ?
•
*RST Condition: Since *RST places the multimeter in the idle state, executing
FETCh? after a *RST generates the “Data corrupt or stale” error.
Example Transferring Stored Readings to Output Buffer
dimension array !Dimension computer array to store 100
readings.
CONF:VOLT:DC !Function: DC voltage; stand-alone
multimeter.
SAMP:COUN 100 !100 readings per trigger (stand-alone
multimeter only).
INIT !Store readings in mainframe memory;
trigger source is IMMediate by default.
FETC? !Place readings in output buffer.
enter statement !Enter readings into computer.
139 Command Reference Chapter 5