Data Translation DT9857, User Manual, Page: 53 / 192

Wiring Signals
53
Connecting Counter/Timer Signals
The DT9857 and DT9857E modules provide a general-purpose counter/timer (C/T 0) that you
can use to perform the following operations:
• Event counting
• Up/down counting
• Pulse width/period measurement
• Edge-to-edge measurement
• Continuous edge-to-edge measurement
• Pulse output (continuous, one-shot, and repetitive one-shot)
The C/T signals are available through the Digital connector on the DT9857 and DT9857E
modules. You can access these signals using the STP25 screw terminal panel, described on
page 47 .
Event Counting
Figure 23 shows how to connect counter/timer signals to the STP25 screw terminal panel to
perform an event counting operation on C/T 0 using an external gate.
The counter counts the number of rising edges that occur on the Counter 0 Clock input when
the Counter 0 Gate signal is in the active state (as specified by software). Refer to
page 95 for
more information on event counting operations.
Figure 23: Connecting Counter/Timer Signals for an
Event Counting Operation Using an External Gate
Signal
Source
Counter 0 Clock
Digital Ground
External
Gating
Switch
14
12
Counter 0 Gate
16
10
Digital Ground
STP25
(Connected to the DT9857 or DT9857E)