Xembedded XVME-689-VR7, Руководство пользователя

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Programming
4-1
Chapter 4 Programming
Memory Map
The preliminary memory map of the XVME 689-VR7 as seen by the CPU is shown below. The
I/O designation refers to memory which is viewed as part of the AT bus or as part of VMEbus
depending on how the Universe is programmed.
XVME 689-VR7 MEMORY MAP
Table 4-1 Memory Map
ADDRESS RANGE (HEX) SIZE DEVICE
FFFC0000 - FFFFFFFF 256K SYSTEM BIOS
end of DRAM -FFFBFFFF xxxK I/O MEMORY**
00100000 – end of DRAM xxxK DRAM *
000F0000 – 000FFFFF 64K SYSTEM BIOS
000E0000 – 000EFFFF 64K SYSTEM BIOS
000D8000 – 000DFFFF 32K Universe Real Mode Window
000D0000 – 000D7FFF 32K Open memory block
000CC000 – 000CFFFF 16K Open memory block
000C0000 – 000C7FFF 32K VGA BIOS
000A0000 – 000BFFFF 128K VGA DRAM MEMORY
00000000 – 0009FFFF 640K DRAM
*See Intel 6300ESB data sheet for a description for optional settings for setting memory holes or
gaps within Memory map area
**The PCI devices are located at the very top of memory just below the system BIOS.
I/O Map
This Preliminary I/O map for the XVME 689-VR7 contains I/O ports of the IBM AT
architecture plus some additions for PCI I/O registers and Xembedded specific I/O
registers.
Hex Range Device
000-01F DMA controller 1, 8237A-5 equivalent
020-021 Interrupt controller 1, 8259 equivalent
022-023 Available
025-02F Interrupt controller 1, 8259 equivalent (note 3)
040-05F Timer, 8254-2 equivalent
060-06F 8742 equivalent (keyboard)
070-07F Real Time Clock bit 7 NMI mask (note 3)
080-091 DMA page register (note 3)
92 Fast GateA20 and Fast CPU Init
93-9F DMA page register (note 3)
0A0-0BF Interrupt controller 2, 8259 equivalent (note 3)