2-30
SIMATIC PC RI25/45, Technical Description
C79000-G7076-C808-01
2.10 Interrupt and DMA Assignments
Interrupt
Description
NMI
Expansion slots signal I/O Channel Check 2
IRQ 0
Internal Timer (System clock)
IRQ 1
Keyboard buffer full
IRQ 2
Cascading of interrupt controller 2
IRQ 3
Serial port 2 (COM 2) can be enabled via Setup
IRQ 4
Serial port 1 (COM 1/TTY) can be enabled via Setup
IRQ 5
MPI port can be enabled via Setup
IRQ 6
Floppy
IRQ 7
Parallel port 1 (Printer port LPT 1/EPP/ECP) can be
enabled via Setup
IRQ 8
Battery-backed real-time clock
IRQ 9
VGA controller usually unassigned
IRQ 10
unassigned
IRQ 11
unassigned
IRQ 12
PS/2 Mouse/ keyboard trackball can be enabled via
Setup if no need for mouse or trackball function
IRQ 13
Arithmet. coprocessor - error
IRQ 14
Primary IDE interface can be enabled via Setup
IRQ 15
Secondary IDE interface (only necessary for special
configuration versions) can be enabled via Setup
DMA Channel
Data transfer
Description
0
8 / 16 bit
free
1
8 / 16 bit
free
2
8 / 16 bit
Floppy
3
8 / 16 bit
free
4
Cascading of DMA controller
5
16 bit
free
6
16 bit
free
7
16 bit
free
Interrupt
Assignments
DMA
Assignments
Motherboard