Advantech UNO-4672, Руководство пользователя

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UNO-4672 User Manual 30
2.12 Onboard Isolated Counter/Timer
The UNO-4672 uses one 82C54 programmable timer/counter chip that
includes three independent 16-bit down counters: counter 0, counter 1 and
counter 2. Counter 0 and counter 1 are for users, and counter 2 is specified
for the system and can’t be used by user. Each counter has clock input, gate
input and pulse output. They can be programmed to count from 2 up to
65535 or cascaded into one 32-bit counter.
The UNO-4672 has two isolated counter input channels designated DI1
and DI3 with two isolated output channels designated DO2 and DO3.
Therefore, you can set each counter of 82C54 as counter function or timer
function.
2.12.1 Counter/Timer Control Register
The Counter/Timer Control Register controls the function and status of
each counter/timer signal source. Table 2.19 shows the bit map of the
Counter/Timer Control Register. The register is readable/writable register.
While being written, it is used as a control register; and while being read,
it is used as a status register.