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•
Using the DAS-1700 Series with DriverLINX
Keithley DAS-1700 Series
4.
Digital Input—refers to the digital input port as well as 1-bit digital
input (TTL) control signals, such as TGIN.
5.
Digital Output—refers to the digital output port and control signals.
6.
Counter/Timer—refers to the input/output subsystem-specific internal
clock channels for pacing analog input/output.
DriverLINX Modes
Applications use modes in Service Requests to advise DriverLINX on their preferred
hardware data transfer technique. The DriverLINX modes fall into two general
classes:
•
Foreground or synchronous modes. The calling application doesn’t
regain control until DriverLINX completes the Service Request.
DriverLINX supports this mode for simple, single value I/O operations
or software housekeeping functions that DriverLINX can complete
without a significant delay.
•
Background or asynchronous modes. The calling application regains
control as soon as DriverLINX initiates the task. The calling application
must synchronize with the data-acquisition task using status polling or
DriverLINX’s messages (preferred). DriverLINX supports this mode
for buffered data transfers or for commands that require a significant
time to complete.
DriverLINX supports four modes with the DAS-1700 Series for its commands
(Service Requests).
•
Polled Mode—This is a foreground or synchronous operation.
DriverLINX supports this mode for simple, single-value I/O operations
that the data-acquisition board can complete without significant delay.
•
Interrupt Mode—This is a background or asynchronous operation.
DriverLINX transfers data between the computer’s memory and the
data-acquisition board using hardware interrupts and programmed I/O
transfers.
•
DMA Mode—This is a background or asynchronous operation.
DriverLINX programs the data-acquisition board to transfer data
between the computer’s memory and the board.
•
Other Mode—This is a foreground or synchronous operation.
DriverLINX supports this mode for initialization, configuration,
calibration, data conversion, and timebase operations.
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