Digital Equipment Prioris XL 6000 Series, Service Maintenance Manual, Page: 138 / 174

14-1
PRIO
RIS
XL
6000 14
Power Up and Boot Sequence
14
Power On Self Test
Before booting the system, the BIOS performs a power on self test to ensure that the
server is in good condition. The self test begins with a BIOS ROM checksum and
memory check. If an error is encountered during this sequence, the BIOS sends a
beep code. Next, the self test runs a series of tests and displays a countdown
number on the screen. The countdown starts at 230 and ends at 10. Countdown
codes and beep codes can be found in Appendix A.
During countdown, the self test checks the following devices:
•
Unexpected interrupts
•
Option ROMs
•
RAM above 512K
•
Extended memory
•
Cache
•
Real-time clock
•
Keyboard
•
Coprocessor
•
I/O ports
•
Mouse
•
Diskette drive