Manual Number: 00750-903-2
Page 5
Interrupt Mode Options
The WINCOMM8/C will allow each port to have an independent interrupt level or share an inter-
rupt with another port on the adapter. The WINCOMM8/C will even share interrupts with a com-
patible port that is located on another adapter. The WINCOMM8/C can operate in three interrupt
modes. Header E9 determines the interrupt mode for Ports 1-4 and header E10 determines the
interrupt mode for ports 5-8.
“
N
” indicates the (
N
)ormal, single interrupt per port mode. “
S
” indicates the (
S
)hared interrupt
mode, which allows more than one port to access a single IRQ. Any two or more ports can share a
common IRQ by placing the jumpers on the same IRQ setting, and setting the appropriate selections
at E1-E8. Consult your particular software for IRQ selection. If no interrupt is desired, remove the
jumper. “
M
” indicates the inclusion of a 1K ohm pull-down resistor required on one port when
sharing interrupts.
1
2
3
4
5
6
7
8
N S M N S M
E9
E10
Figure 3: Header E9 and E10, Normal IRQ Mode
Set jumpers to “
S
” for shared interrupt mode on all blocks sharing an IRQ except one. Set that port
block for “
M
”. This provides the pull-down resistor circuit that makes IRQ sharing possible. If you
are using more than one WINCOMM8/C or a compatible adapter in a bus, you should only have one
port set to “
M
”. The following example shows all eight ports sharing a single IRQ.
1
2
3
4
5
6
7
8
N S M N S M
E9
E10
Figure 4: Header E9 and E10, Shared IRQ Mode
Set all jumpers to “
S
” if you are using more than one WINCOMM8/C in a bus or you wish to
completely remove the pull-down resistor for hardware compatibility.
Setting the
WINCOMM8/C
in this configuration when it is not accompanied by a pull-down resistor
will prevent the ports from triggering an interrupt
.
1
2
3
4
5
6
7
8
N S M N S M
E9
E10
Figure 5: Header E9 and E10, Sharing IRQs with another adapter
