Measurement Specialties PCI-CTR05 manual Specifications, Digital input / output, Interrupt

Chapter 4

Specifications

Typical for 25 °C unless otherwise specified.

Specifications in italic text are guaranteed by design.

The counter frequency sources and 3.3 V compatibility apply to hardware manufactured at revision 3 and later

The clock input frequency sources and compatibility with a 3.3 V signaling environment that are listed in this specification apply to hardware built at revision 3 and later.

Digital input / output

Table 4-1. Digital I/O specifications

Digital type	Discrete, 5V/TTL compatible
	Output:	74ACT273
	Input:	74LS373
Number of I/O	8 input, 8 output
Configuration	1 bank of 8 as output, 1 bank of 8 as strobed input
Input high voltage	2.0 V min, 7.0 V absolute max
Input low voltage	0.8 V max, –0.5 V absolute min
Output high voltage	3.94 volts min @ -24 mA (Vcc = 4.5 V)
Output low voltage	0.36 volts max @ 24 mA (Vcc = 4.5 V)
Data transfer	Programmed I/O
Power-up / reset state	Digital outputs reset to TTL low
Din strobe	Active low latch enable input, internally pulled high through 10 KOhm resistor
Din strobe pulse width high/low	15 nS min
Data setup to Din strobe	5 nS min
Data hold from Din strobe	20 nS min

Interrupt

	Table 4-2. Interrupt specifications
Number of user interrupts	One
PCI Interrupt	PCI INTA# - mapped to IRQn via PCI BIOS at boot-time
Interrupt enables	External: IRQ ENABLE, active low, disabled by default through internal
	resistor to TTL high) and programmable through PCI9030-AA60PI; 0 =
	disabled, 1 = enabled (default)
Interrupt sources	External: IRQ IN, polarity programmable through PCI9030-AA60PI;
	1 = active high, 0 = active low (default).
	IRQ IN maps to PLX 9030 LINT1.

4-1