Detailed descriptions
16.4 System resources
SIMATIC Rack PC 847B
156
Operating Instructions, 06/2008, A5E02203168-01
16.4.2
System resources used by the BIOS/DOS
The following table describes the system resources for the factory state of the device.
16.4.2.1
I/O address allocation
I/O address (hex)
from
to
Size
(bytes)
Description of the basic function
Possible alternative
function
0000
000F
16
DMA controller
0010
001F
16
Motherboard resources
0020
0021
2
Programmable interrupt controller
0022
003F
30
Motherboard resources
0040
0043
4
System timer
0044
005F
28
Motherboard resources
0060
0060
1
Keyboard controller
0061
0061
1
System loudspeaker
0062
0063
2
Motherboard resources
0064
0064
1
Keyboard controller
0067
006F
9
Motherboard resources
0070
0075
6
System CMOS/real-time clock
0076
0080
11
Motherboard resources
0081
008F
15
DMA controller
0090
009F
16
Motherboard resources
00A0
00A1
2
Programmable interrupt controller
00A2
00BF
30
Motherboard resources
00C0
00DF
32
DMA controller
00E0
00EF
16
Motherboard resources
00F0
00FE
15
Numeric data processor
0110
016F
96
Not used
0170
0177
8
Secondary EIDE channel
0178
01EF
120
Not used
01F0
01F7
8
Primary EIDE channel
Switchable in Setup,
then free
01F8
01FF
8
Not used
0200
0207
8
Reserved for game port
0208
02E7
224
Not used
02E8
02EF
8
Reserved
02F8
02FF
8
COM2
Switchable in Setup,
then free