Keithley 6485, Руководство пользователя

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6-2 Buffer and Sweeps Model 6485 and 6487 User’s Manual
Buffer operations
The Model 6485 has a buffer to store from one to 2,500 readings. The Model 6487 buffer
can store from one to 3,000 readings. Both instruments also store overflow readings and a
timestamp, and each Model 6487 reading includes the voltage source value. The timestamp
for each reading is referenced to the time the measure/store process is started. In addition,
recalled data includes statistical information (maximum, minimum, peak-to-peak, average
and standard deviation).
The buffer fills with the specified number of readings and stops. Readings are placed in
the buffer after any filters and/or math operations have been performed. Math operations
include relative, mX+b, m/X+b, LOG, or limits (see
Section 5 ).
Buffered data is overwritten each time the storage operation is selected. The data is volatile
— it is not saved through a power cycle.
Measurement function changes are permissible during the storage process. Note however,
that the statistics will be based on the readings of the different measurement functions.
Store
To store readings, set up the instrument for the desired configuration, then press CONFIG
followed by STORE. Set the number of readings to store (1-2500, Model 6485; 1-3000,
Model 6487), and press ENTER. Press the STORE key to start data storage. The asterisk
(*) annunciator turns on to indicate that the data storage operation is active. To abort stor-
age while active, press EXIT.
Recall
To view stored readings and buffer statistics, press RECALL, then use the RANGE and
cursor keys to navigate through the reading numbers and buffer statistics, reading values,
voltage source values (Model 6487 only), and timestamps. (Use the RANGE keys to
scroll through statistics and reading values; use the cursor keys to select among readings,
Model 6487 voltage source values, and timestamps.) The BUFFER annunciator will be
on while readings are being recalled. Press EXIT to return to normal display.
NOTE For the Model 6487, if the voltage source was in compliance when the reading
was acquired, the recalled front panel SRC: display will show the voltage value
dimmed. Over the GPIB, a value of -999 returned for the voltage source element
indicates that the source was in compliance.