HP Vectra VL6 6 Technical Reference Manual page 25

FDC
RTC
Keyboard and Mouse
Controller
Serial EEPROM
The integrated flexible disk controller (FDC) supports any combination of
two of the following: tape drives, 3.5-inch flexible disk drives, 5.25-inch
flexible disk drives. It is software and register compatible with the 82077AA,
and 100% IBM compatible. It has an A and B drive-swapping capability and a
non-burst DMA option.
The real-time clock (RTC) is 146818A-compatible. With an accuracy of
20 ppm (parts per million). The configuration RAM is implemented as 256
bytes of CMOS memory.
The computer has an 8042-based keyboard and mouse controller. The
connector pin layouts are shown on page 55. The Power-On keyboard is
described on page 31.
This is the non-volatile memory which holds the values for the Setup
program (they are no longer stored in the CMOS memory).
2 System Board
Chip-Set
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