Measurement Computing PCI-DAS08, Руководство пользователя

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PCI-DAS08 User's Guide Specifications
Digital input / output
Table 4-2. Digital I/O specifications
Parameter Specification
Digital type (main connector):
Output 74ACT273
Input 74LS244
Configuration
3 fixed input, 4 fixed output
Number of channels 7
Output high 3.94 volts min @ -24 mA (Vcc = 4.5 V)
Output low 0.36 volts max @ 24 mA (Vcc = 4.5 V)
Input high 2.0 volts min, 7 volts absolute max
Input low 0.8 volts max, -0.5 volts absolute min
Interrupts INTA# - mapped to IRQn via PCI BIOS at boot-time
Interrupt enable Programmable through PCI controller:
0 = disabled, 1 = enabled (default)
Interrupt sources External source (EXT INT)
Polarity programmable through PCI controller:
1 = active high, 0 = active low (default)
Counter section
Table 4-3. Counter specifications
Parameter Specification
Counter type 82C54 device
Configuration 3 down counters, 16-bits each
Counter 0 - User counter 1 Source: Available at user connector (CTR1CLK)
Gate: Available at user connector (CTR1GATE)
Output: Available at user connector (CTR1OUT)
Counter 1 - User counter 2 Source: Available at user connector (CTR2CLK)
Gate: Available at user connector (CTR2GATE)
Output: Available at user connector (CTR2OUT)
Counter 2 - User counter 3 or
Interrupt Pacer Source: Buffered PCI clock (33 MHz) divided by 8.
Gate: Available at user connector (CTR3GATE)
Output: Available at user connector (CTR3OUT) and may be
software configured as Interrupt Pacer.
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 0.8 V max
Input high voltage 2.0 V min
Output low voltage 0.4 V max
Output high voltage 3.0 V min
4-2