Appendix A
Specifications
©
National Instruments Corporation
A-15
Digital I/O
Number of channels ............................... 8 input/output
Compatibility ......................................... TTL/CMOS
Power-on state........................................ Input (high-impedance)
Data transfers ......................................... DMA, interrupts,
programmed I/O
Input buffer ............................................ 2,000 bytes
Output buffer.......................................... 2,000 bytes
Transfer rate (1 word = 8 bits) ............... 10 Mwords/s
Timing I/O
Number of channels ............................... 2 up/down counter/timers,
1 frequency scaler
Resolution
Counter/timers ................................ 24 bits
Frequency scaler ............................. 4 bits
Compatibility ......................................... TTL/CMOS
Base clocks available
Counter/timers ................................ 20 MHz, 100 kHz
Frequency scaler ............................. 10 MHz, 100 kHz
Table A-7.
Digital logic levels
Level
Min
Max
Input low voltage
Input high voltage
Input low current (V
in
= 0 V)
Input high current (V
in
= 5 V)
0.0 V
2.0 V
—
—
0.8 V
5.0 V
–320
µ
A
10
µ
A
Output low voltage (I
OL
= 24 mA)
Output high voltage (I
OH
= 13 mA)
—
4.35 V
0.4 V
—