AT&T PC 6300 - Page 41

n
n
n
n
n
n
SYSTEM OVERVIEW
n
n
n
n
n
n
n
n
n
n
n
The Motherboard ROM contains the Resident Diagnostics and
Bootstrap Loader programs. Two EPROM chips provide a total of
16 KB of Programmable Read-Only Memory. The ROMs physically
occupy addresses FOOOO to FFFFF. Following power-up or reset,
the 8086 CPU always begins execution at location FFFFO that
contains a jump instruction. This jump instruction directs the
system to the initial Resident Diagnostic routine and then to the
Bootstrap Loader. The ROMs also contain drivers for the
Keyboard, Mini-Floppy Disk, Hard Disk, and other peripherals
along with initialization programs for Large Scale Integration
(LSI) chips.
2-17