ADLINK Technology ReadyBoard 620, Reference Manual

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Chapter 3 Hardware
ReadyBoard 620 Reference Manual 17
Memory Map
The following table provides the common PC/AT memory allocations. Memory below 000500h is used by
the BIOS. Refer to Table 3-2 .
I/O Address Map
Table 3-3 lists the I/O addresses.
Table 3-2. Memory Map
Base Address Function
00000000h - 0009FFFFh Conventional Memory
000A0000h - 000AFFFFh Graphics Memory
000B0000h - 000B7FFFh Mono Text Memory
000B8000h - 000BFFFFh Color Text Memory
000C0000h - 000C7FFFh Standard Video BIOS
000D0000h - 000DFFFFh Reserved for Extended BIOS
000E0000h - 000FFFFFh System BIOS Area (Storage and RAM Shadowing)
00100000h - Top of DRAM Extended Memory (If on-board VGA is enabled, then the amount of
memory assigned is subtracted from extended memory.)
FFF80000h - FFFFFFFFh System Flash
Table 3-3. I/O Address Map
Address (hex) Subsystem
000-00F Primary DMA Controller
020-021 Master Interrupt Controller
040-043 Programmable Interrupt Timer (Clock/Timer)
060-06F Keyboard Controller
070-07F CMOS RAM, NMI Mask Reg, RT Clock
080-09F DMA Page Registers
092 Fast A20 Gate and CPU Reset
094 Motherboard Enable
102 Video Subsystem Register
0A0-0BF Slave Interrupt Controller
0C0-0DF Slave DMA Controller #2
0F0-0FF Math Coprocessor
1F0-1F8 IDE Hard Disk Controller
201 Watchdog Timer (WDT)
278-27F Parallel Printer
2E8-2FF Serial Port 4 (COM4)
2F8-2FF Serial Port 2 (COM2)
378-37F Parallel Port (Standard and EPP)
3C0-3DF VGA
3E8-3EF Serial Port 3 (COM3)
3F0-3F7 Floppy Disk Controller