Appendix D. 82C54 Counter Chip Function; The Intel 82C54 - Advantech MIC-3716 Manual

Appendix D. 82C54 Counter Chip
D.1 The Intel 82C54
The MIC-3716 uses one Intel 82C54 compatible programmable
interval timer/counter chip. The popular 82C54 offers three
independent 16-bit counters, counter 0, counter 1 and counter 2. Each
counter has a clock input, control gate and an output. 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
MIC-3716 provides 10 MHz input frequencies to the counter chip
from an on-board crystal oscillator.
Counter 0
On the MIC-3716, counter 0 can be a 16-bit timer or an event counter,
selectable by users. When the clock source is set as an internal source,
counter 0 is a 16-bit timer; when set as an external source, then
counter 0 is an event counter and the clock source comes from
CNT0_CLK. The counter is controlled by CNT0_GATE. When
CNT0_GATE input is high, counter 0 will begin to count.
Counter 1 & 2
Counter 1 and counter 2 of the counter chip are cascaded to create a
Function
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