Measurement Computing PC-CARD-DAS16/330 - Manual (Page 22)

PC-CARD-DAS16/330 User's Guide Specifications
Interrupt
Table 7. Interrupt specifications
Interrupts Programmable: levels 2 – 15
Interrupt enable Programmable (default = disabled)
External (External Interrupt)
A/D End-of-channel-scan
A/D FIFO-not-empty
A/D FIFO-half-full
Interrupt sources
A/D Pacer
Counter
Table 8. Counter specifications
Counter type 82C54
Configuration 3 down counters, 16 bits each
Source: Programmable external (Ctr 1 Clk) or 100kHz internal source
Gate: Available at connector (Ctr 1 Gate), pulled to logic high via 10k
resistor (See Note 2).
Counter 1 - User counter
Output: Available at connector (Ctr 1 Out)
Source: Programmable, 1 MHz or 10 MHz internal source
Gate: Available at connector (A/D Pacer Gate), pulled to logic high via
10 k resistor.
Counter 2 - ADC Pacer Lower
Divider
Output: Chained to Counter 3 Clock
Source: Counter 2 Output
Gate: Internal
Counter 3 - ADC Pacer Upper
Divider
Output: Programmable as ADC Pacer clock. Available at user connector
(ADC Pacer 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 0.8 V max
Input high voltage 2.0 V min
Output low voltage 0.4 V max
Output high voltage 3.0 V min
Crystal oscillator frequency 10 MHz
Frequency accuracy 50 ppm
Note 2: If you are not driving the gate of User Counter 1, it is strongly recommended that it be connected
to +5V (VDD).
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