Counters

The PCI-1784 has four independent 32-bit counters. The maximum quadrature input rate is 2 MHz, and the maximum input rate in counter mode is 8 MHz. You can individually configure each counter for quadrature decoding, pulse/direction counting or up/down counting.

Digital Input and Interrupts

The PCI-1784 provides four digital input channels. Each channel accepts digital input as an index input for a rotary encoder or as a home sensor input for a linear encoder. The card can generate an interrupt to the system based on a signal from its digital inputs, overflow/underflow and over-compare/under-compare of its counters, or on a programmed time interval. It can repeatedly generate interrupts at any time interval you specify, from 20 micro second to 51 second. These interrupts let you precisely monitor the speed of a control system.

Flexible Digital Output function

The PCI-1784 provides four digital output channels. Each channel accepts digital output as a normal TTL output for a rotary encoder, or as an indicated output with pulse/level mode for a linear encoder. The PCI- 1784 can generate an indicated output based on a signal from over- compare/under-compare of its counters. The pulse width of an indicated output is depends on the counter clock or clear interrupt.

Special Shielded Cable for Noise Reduction

The PCL-10137H shielded cable is specially designed for the PCI-1784 for reducing noise. Its wires are all twisted pairs, and the input signals and output signals are separately shielded, providing minimal cross talk between signals and the best protection against EMI/EMC problems.

Keeping the Counter Values and the Output Status after system reset

Users can independently use the four counter channels. When the system is hot reset (power not shut down), the PCI-1784 can either retain the last counter values and the output status, or return to its

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Advantech PCI-1784 specifications Counters, Digital Input and Interrupts, Flexible Digital Output function