Specifications

12 PCL-846 User's Manual
In this mode, each of the four ports can have IRQ channels set
individually. For each port, select an IRQ which is not already in use
by another card in the system. The mapping of jumpers to ports is as
shown below.
Port 1 à JP11
Port 2 à JP12
Port 3 à JP13
Port 4 à JP14
Shared IRQ Mode (JP11)
Select an IRQ which is not already in use by another card in the
system. If you are installing more than one PCL-846, set them to
different IRQ numbers. Jumper Bank JP11 controls the card IRQ.
Simply place the jumper on the desired interrupt level as shown in the
following figure.
Interrupt Status Register Setup
(S2, Vector address)
This featur e on the PCL-846 is utiliz ed in the IRQ shar ing mode onl y.
When data arrives at one of the four ports, it generates an interrupt in
the interrupt register. T he PC softw are can read this, and identify
immedia tely whic h por t g ener ated the interrupt. This sa v es time , and
makes programming easier .
When a data bit of the interrupt status register is set to 0, the corre-
sponding port is selected to generate an interrupt in DOS and
WIN 3.x, the corresponding interrupt register for Win 95/NT is 1. If
the bit is 1, then no inter rupt is g ener ated. The follo wing ta ble sho ws
JP11