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Chapter 9: Specifications
Manual Number: 00650-004-5
Page 9-3
Digital I/O
(8 Bits on Main 37-Pin D Connector)
Inputs:
Logic high: 2.0 to 5.0 VDC at 20
m
A maximum.
Logic low: -0.5 to +0.8 VDC at -0.2 mA maximum.
Outputs:
Logic high: 2.4V minimum at -0.4 mA source.
Logic low: 0.5V maximum at 8.0 mA sink.
(24 Bits on Auxiliary 37-Pin D Connector)
Inputs:
Logic high: 2.0 to 5.0 VDC at 10
m
A maximum
Logic low: -0.5 to +0.8 VDC at -10
m
A maximum.
Outputs:
Logic high: 2.4V minimum at 200
m
A source.
Logic low: 0.5V maximum at 1.7 mA sink.
Interrupt Channel
Levels:
Levels 2 through 7, and 10-12, 14, and 15; jumper selectable.
Enable:
The two IRQ sources (End of Conversion, CTR2 timeout) are individually enabled via control bits in
the BASE+0 control register. The IRQ is latched, and the state of the latch is reported in the INT
bit of the status register. Reading to the control register clears the IRQ latch and prepares the card
to generate the next IRQ.
Programmable Timer
Type:
82C54-2 programmable interval timer.
Counters:
Three 16-bit down counters, two permanently concatenated as a pacing counter with a 1MHz
clock. One is uncommitted but driven by the 1MHz clock or an external clock source.
Output Drive:
2.2mA at 0.45V (5 LSTTL loads).