Keithley KPCI-3101 Series, Руководство пользователя

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2-4 Principles of Operation KPCI-3101 — KPCI-3104 Series User’s Manual
Specifying one or more channels
On the KPCI-3101–4 Series board, you can read data from one or more analog input channels
using an analog input channel list. You can group the channels in the list sequentially (either
starting with 0 or with any other analog input channel) or randomly. You can also specify a sin-
gle channel or the same channel more than once in the list.
Using DriverLINX software, specify the channels in the order you want to sample them. The
analog input channel list corresponds to the Channel-Gain List FIFO (first-in, first-out buffer) on
the board. You can enter up to 1,024 entries in the channel list. The channels are read in order
(using continuous paced mode or triggered scan mode) from the first entry to the last entry in the
channel list. You can read the channels in the channel list up to 256 times per trigger (for a total
of 262,144 samples per trigger) using triggered scan mode. Refer to
page 2-7 for more informa-
tion on the supported conversion modes.
Specifying digital input lines in the analog input channel list
In addition to the analog input channels, the KPCI-3101–4 Series board allows you to read 16
digital I/O lines (Port A, lines 0 to 7 and Port B, lines 0 to 7) using the analog input channel list.
This feature is particularly useful when you want to correlate the timing of analog and digital
events.
To read these 16 digital I/O lines, specify channel 0 in the DriverLINX analog input channel list
with a special gain modifier. Refer to the DriverLINX Analog I/O Programming Guide, provided
with DriverLINX.
NOTE
If channel 0 is programmed with digital capabilities and is the only
channel in the channel-gain list, the board can read this channel at a
rate of 3MSamples/s. Refer to the DriverLINX Analog I/O Programming
Guide, provided with DriverLINX.
The digital channel is treated like any other channel in the analog input channel list; therefore,
all the clocking, triggering, and conversion modes supported for analog input channels are sup-
ported for these digital I/O lines, if you specify them in this manner.
Input ranges and gains
Each channel on the KPCI-3101, KPCI-3102, KPCI-3103, and KPCI-3104 board can measure
unipolar and bipolar analog input signals. A unipolar signal is always positive (0 to 10V on a
KPCI-3101–4 Series board), while a bipolar signal extends between the negative and positive
peak values (±10V on a KPCI-3101–4 Series board).
Through software, specify the range as 0 to 10V for unipolar signals or
−
10V to +10V for bipo-
lar signals. Note that you specify the range for the entire analog input subsystem, not the range
per channel.