1 8
UNO-2050 User's Manual
2.6 On-board Isolated Counter/Timer
The UNO-2050 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-2050 has 2 isolated counter input channels designated DI6
and DI7 or 2 isolated timer output channels designated DO6 and DO7.
Therefore, you can set each counter of 82C54 as counter function or
timer function.
Counter/Timer Control Register
The Counter/Timer Control Register controls the function and status
of each counter/timer signal source. Table 2-9 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.
Table 2-9: Counter/Timer control register bit map
Base Address
7
6
5
4
3
2
1
0
Base+07H R/W
Interrupt Flag/Clear Register
CTR1F
CTR0F
Base+08H R/W
82C54 Chip Counter0 Register
Base+09H R/W
82C54 Chip Counter1 Register
Base+0BH R/W
82C54 Chip Control Register
Base+0CH R/W
Counter0 Start Control / Output Status Register
CTR0Out
CTR0Gate
Base+0DH R/W
Counter1 Start Control / Output Status Register
CTR1Out
CTR1Gate
Base+0EH R/W
Counter0 Setting Register
CTR0IntSet CTR0OutSet CTR0GateSet CTR0CLKSet
Base+0FH R/W
Counter1 Setting Register
CTR32Set S1
S0
CTR1IntSet CTR1OutSig CTR1GateSig CTR1CLKSig
