Chapter 4 Specifications; Digital Input/Output; Counter - Measurement Computing PC-CARD-D24/CTR3 User Manual

Specifications
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.

Digital input/output

Digital type
Configuration
Number of channels
Output high
Output low
Input high
Input low
Power-up / reset state
Interrupts
Interrupt enable
Interrupt sources

Counter

Counter type
Configuration
Counter 1 - Independent user
counter
Counter 2 - Independent user
counter
Counter 3 - Independent user
counter
Clock input frequency
High pulse width (clock input)
Low pulse width (clock input)
Gate width high
Gate width low
Input low voltage
Input high voltage
Output low voltage
Output high voltage
Table 1. Digital I/O specifications
82C55
2 banks of 8, 2 banks of 4, programmable by bank as input or output
24 I/O
3.0 volts min @ -2.5 mA
0.4 volts max @ 2.5 mA
2.0 volts min, 5.5 volts absolute max
0.8 volts max, -0.5 volts absolute min
Input mode (high impedance)
Programmable levels 2-15
Programmable
Programmable:
External (Ext Int)
Internal (counter 1 output, counter 2 output, counter 3 output, 82C55 port C bit C0 or
bit C3)
Table 2. Counter specifications
82C54
3 down counters per 82C54, 16 bits each
Source: Programmable internal 10 MHz or external (CTR1 CLK)
Gate: External (CTR1 Gate), pulled high (enabled) by 10 k resistor
Output: Available at user connector (CTR1 Out), may also be programmed to
connect to counter 2 clock.
Source: Programmable internal 10 MHz , external (CTR2 CLK) or CTR1 Out
Gate: External (CTR2 Gate), pulled high (enabled) by 10 k resistor
Output: Available at user connector (CTR2 Out), may be programmed to
connect to counter 3 clock
Source: Programmable internal 1 MHz , external (CTR3 CLK) or CTR2 Out
Gate: External (CTR3 Gate), pulled high (enabled) by 10k resistor
Output: Available at user connector (CTR3 Out)
10 MHz max
30 ns min
50 ns min
50 ns min
50 ns min
0.8 V max
2.0 V min
0.4 V max
3.0 V min
16
Chapter 4