Technical data

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Address Resources
DMA Channels
The system board uses Direct Memory Address (DMA) channels to exchange data without accessing
the CPU. Some channels are assigned for specific use by the system, as defined below. Each DMA
channel appropriates full 32-bit processing. For an ISA bus, channels 0 through 3 are 8-bit and
channels 4 through 7 are 16-bit channels.
DMA
Assignment DMA Assignment
0 LPT 4 Cascade input for 0-3
1 Crystal CS4236B Controller 5 Spare
2 Floppy Controller 6 Spare
3 Crystal CS4236B Controller 7 Spare
Input/Output Addresses
The following table lists a small subset of the reserved I/O addresses.
Address
Device
0278 - 027F Parallel Port LPT2
02E8 - 02EF Serial Port COM4
02F8 - 02FF Serial Port COM2
0378 - 037F Parallel Port LPT1
03B0 - 03BF Monochrome Display/Printer Adapter
03C0 - 03CF Enhanced Graphics Adapter (EGA/VGA)
03D0 - 03DF Color/Graphics Monitor Adapter (CGA/MCGA)
03E8 - 03EF Serial Port COM3
03F0 - 03F7 I/O Controller
03F8 - 03FF Serial Port COM1
Memory Address Map
The following table lists the memory address map assignments.
Memory Address
Size Assignment
00000000 - 0009FFFF 640K System board memory
000A0000 - 000BFFFF 128K Video memory
000C0000 - 000C7FFF 32K Video ROM
000C8000 - 000DFFFF 96K Available I/O Adapter ROM
000E0000 - 000EFFFF 64K BIOS ROM and PCMCIA
000F0000 - 000FFFFF 64K BIOS ROM
00100000 - 1FFFFFFF 511M Expansion memory
20000000 - 3FFFFFFF ----- Reserved