Digital Equipment Prioris XL 6000 Series, Service Maintenance Manual

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Server Management
4-10
Recovery Port-80 Codes and Countdown Codes
These codes are displayed during a recovery boot process. During this process,
a diskette in drive A is booted and a BIOS image is automatically installed.
Port 80
Codes Countdown
Codes Description
02h Disable internal cache
08h Disable DMA controller #1 and #2, disable interrupt controller #1 and
#2, and reset video display
13h Initialize all chipset registers
15h 900 Initialize system timer
1Bh 800 Real mode base 64 KB memory test
20h 700 16 KB base RAM test
23h 650 Setup interrupt vectors
40h 600 Test memory in virtual mode
65h 500 Initialize 8237 DMA controller
67h 400 8259 interrupt controller test
80h 300 Unmask diskette, keyboard, and timer interrupts
88h 200 Floppy unit initialization
A0h 100 Cache enable
00h 000 Boot OS