Measurement Computing CIO-DAS08-AOH - Manual (Page 25)

Counter section
Counter type 82C54
Configuration 3 down counters, 16 bits each
Counter 0 - independent, user configurable
Source: user connector (Counter 0 In)
Gate:
tied high through 10k (enabled)
Output: user connector (Counter 0 Out)
Counter 1 - independent, user configurable
Source: user connector (Counter 1 In)
Gate:
user connector (Gate 1)
Output: user connector (Counter 1 Out)
Counter 2 - independent, user configurable
Source: 1MHz (from 10MHz Xtal via divide-by-ten) or PC SysClk (via divide by 2 circuit)
selectable by jumper
Gate: user connector (Gate 2)
Output: user connector (Counter 2 Out)
Clock input frequency 10 Mhz max
High pulse width (clock input) 30 ns min
Low pulse width (clock input) 50 ns min
Gate width high 50 ns min
Gate width low 50 ns min
Input low voltage 0.8V max
Input high voltage 2.0V min
Output low voltage 0.4V max
Output high voltage 3.0V min
Environmental
Operating temperature range 0 to 50°C
Storage temperature range
−
20 to 70°C
Humidity 0 to 95% non-condensing
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