Microsoft Advantech UNO-3074 User Manual

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UNO-3074 User Manual
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2.7  Onboard Isolated Counter/Timer
The UNO-3074 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-3074 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.
2.7.1 Counter/Timer Control Register
The Counter/Timer Control Register controls the function and status of 
each counter/timer signal source. Table 2.11 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 2.11: Counter/Timer Control Register Bit Map
Base 
Address
7
 
6
 
5
 
4
 
3
 
2
 
1
 
0
207H  R/W Interrupt Flag/Clear Register
CTR1F CTR0F
208H  R/W 82C54 Chip Counter0 Register
209H  R/W 82C54 Chip Counter1 Register
20BH  R/W 82C54 Chip Control Register
20CH  R/W Counter0 Start Control / Output Status Register
CTR0
Out 
CTR0
Gate
20DH  R/W Counter1 Start Control / Output Status Register
CTR1
Out
CTR1
Gate
20EH  R/W Counter0 Setting Register
CTR0
IntSet
CTR0
OutSet
CTR0
GateSet
CTR0
CLKSet
20FH  R/W Counter1 Setting Register
CTR3
2Set
 S1
 S0
CTR1
IntSet
CTR1
OutSet
CTR1
GateSet
CTR1
CLKSet