CR1000 Manual - Campbell Scientific

Section 4. Quickstart Tutorial
Figure 9: Location of RS-232 ports
Figure 10: Use of RS-232 and digital I/O when reading RS-232 devices
4.1.4 Digital I/O Ports
The CR1000 has eight digital I/O ports selectable as binary inputs or control
outputs. These are multi-function ports. Edge timing, switch closure, and highfrequency
pulse functions are introduced in Pulse Sensors (p. 38) and discussed at
length in Pulse (p. 312). Other functions include device-driven interrupts,
asynchronous communications and SDI-12 communications. Figure Control and
Monitoring with Digital I/O (p. 42) illustrates a simple application wherein digital
I/O ports are used to control a device and monitor the state (whether on or off) of
the device.
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