18 MultiModemISI Hybrid Series, ISIHI-2S
Hardware Installation
Determine Current System Settings
When you install a device into your computer, the processor must have a means of
routing information to and from the device, and the device must have a means of gaining
the processor’s attention. Input/Output (I/O) addresses route information to and from the
device. Interrupt Requests (IRQs) gain the processor’s attention. The ISIHI-2S card
requires eight I/O addresses and one IRQ value that are not used by any other device in
your system. When selecting a unique base I/O address, be sure the next address also
is unused. To determine your system’s current setting, refer to Appendix A and B.
If you are certain these settings are not already in use, continue with the hardware
installation. Each card is shipped with the IRQ set at 10 and the base I/O address set at
210 hex. Check your system’ssettings to see if these values can be used. If the defaults
are already in use, select a unique IRQ and I/O address and record them below for future
reference.
I/O address _____________ IRQ ___________________

Recommended Base I/O Address and IRQ Values

ISIHI-2S Base I/O Address IRQ

Initial 8 port board 210h 10
First 8 port upgrade 220h 11
Second 8 port upgrade 230h 12
Third 8 port upgrade 240h 15