System Resources and Maps
EPM-15 Reference Manual
40
Interrupt Configuration
The EPM-15 has the standard complement of PC type interrupts. Three non-shared interrupts are
routed to the PC/104 bus, and up to four IRQ lines can be allocated as needed to PCI devices.
There are no interrupt configuration jumpers. All configuration is handled through CMOS Setup.
Table 14: EPM-15 IRQ Settings
z
= default setting
|
= allowed setting
IRQ
Source
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Timer 0
z
Keyboard
z
Slave PIC
z
COM1
|
z
|
{
|
|
|
COM3
|
|
{
|
|
|
|
COM4
|
|
|
|
|
|
|
Floppy
z
RTC
z
Mouse
z
Math Chip
z
Pri. IDE
z
LPT1
|
|
|
|
|
|
|
CPU Temp
|
|
|
|
|
|
ISA IRQ3
|
ISA IRQ4
|
ISA IRQ10
|
PCI
INTA#
|
|
|
z
|
PCI
INTB#
|
|
|
z
|
PCI
INTC#
|
|
|
z
|
PCI
INTD#
|
z
|
|
|
Table 15: PCI Interrupt Settings
z
= default setting
|
= allowed setting
PCI Interrupt
Source
INTA#
INTB#
INTC#
INTD#
Ethernet
z
Audio
z
USB
z
Notes:
If your design needs to use interrupt lines on the PC/104 bus, IRQ10 is recommended. (IRQ3 and
IRQ4 are normally used by COM ports on the main board.)
Though the EPM-15 is not equipped with a standard keyboard (IRQ1), floppy disk (IRQ6), or
mouse (IRQ12), the BIOS infrastructure makes it appear they exist for DOS and older operating
systems. Though these devices use USB interrupts, legacy IRQs are created via software.
ACPI uses IRQ9. IRQ9 should not be assigned to other devices if ACPI is enabled.
