Keithley KPCI-3110, User Manual

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2-4 Functional Description KPCI-3110 and KPCI-3116 User’s Manual
Specifying digital input lines in the analog input channel list
In addition to the analog input channels, you can read the two digital I/O channels (16 lines) of
the KPCI-3110 and KPCI-3116 boards using the analog input channel list. This feature is partic-
ularly useful when you want to correlate the timing of analog and digital events.
To read these two digital I/O channels, specify channel 0 in the DriverLINX analog input
channel list. Specify the special code (2
13
) in the gain field to indicate that channel 0 is a 16 bit
digital channel. See “Analog Input Termination Modes” in “Using DriverLINX with Your
Hardware.” The hardware-specific gain code is provided in the DriverLINX channel gain list.
You can enter channel 0 anywhere in the list and can enter it more than once, if desired. 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 3 MSamples/s. Refer to the
Using DriverLINX with your Hard-
ware:Keithley KPCI-3100 manual provided with DriverLINX .
This 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 supported
for these digital I/O lines, if you specify them in this manner.
Performing dynamic digital output operations
Using DriverLINX software, you can enable a synchronous dynamic digital output operation for
the A/D subsystem. This feature is particularly useful for synchronizing and controlling external
equipment.
Two dynamic digital output lines are provided: 0 and 1. These lines are set to a value of 0 on
power up; a reset does not affect the values of the dynamic digital output lines. Note that these
lines are provided in addition to the other 16 digital I/O lines. See
page 2-21 for more informa-
tion on the digital I/O features.
To read these two digital I/O lines, specify channel 0 in the DriverLINX analog input channel
list. Specify its digital capabilities in the Digital Capabilities groups of the Logical Device
Descriptor (channel, channel characteristics, and timing and start/stop trigger events). The
hardware-specific gain code is provided in the DriverLINX channel gain list. You can enter
channel 0 anywhere in the list and can enter it more than once, if desired. Refer to the
Using
DriverLINX with your Hardware: Keithley KPCI-3100 manual 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 3 MSamples/s.
Refer to the Using DriverLINX with your Hard-
ware: Keithley KPCI-3100 manual provided with DriverLINX .
For KPCI-3110 and KPCI-3116 boards, you can specify the following values for the dynamic
digital output lines: 0 (00 in binary format), 1 (01 in binary format), 2 (10 in binary format), or 3
(11 in binary format). Each bit in binary format corresponds to the value to write to the dynamic
digital output line. For example, a value of 1 (01 in binary format) means that a value of 1 is out-
put to dynamic digital output line 0 and value of 0 is output to dynamic output line 1. Similarly,
a value of 2 (10 in binary format) means that a value of 0 is output to dynamic digital output line
0 and value of 1 is output to dynamic output line 1.
For example, assume that the analog input channel list contains channels 5, 6, 7, 8; that dynamic
digital output operations are enabled; and that the values to write to the dynamic digital output
lines are 2, 0, 1, 3.
Figure 2-2 shows this configuration.