Appendix C 82C54 Counter Chip Function; Intel 82C54; C.1 Intel 82C54 - Advantech PCI-1742U User Manual

Appendix C 82C54 Counter Chip

C.1 Intel 82C54

The PCI-1742U uses one Intel 82C54-compatible programmable interval
timer/counter chip. The popular 82C54 chip offers three independent 16-
bit counters, counter 0, counters 1 and 2. You can program each counter
for maximum count values from 2 to 65535.
The 82C54 has a maximum input clock frequency of 10 MHz. The PCI-
1742U provides 10 MHz input frequencies to the counter chip from an
onboard crystal oscillator.
Counter 0
On the PCI-1742U, counter 0 can be a 16-bit timer or an event counter as
chosen by the user. When the clock source is set as an internal source,
counter 0 is a 16-bit timer.
Counter 1 & 2
Counters 1 and 2 of the counter chip are cascaded to create a 32-bit timer
for the pacer trigger. A low-to-high edge of counter 2's output will trigger
an A/D conversion.
PCI-1742U User Manual
Function
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