80
3 System Board (P/Ns D3657-63001 and D3661-63001)
Devices on the ISA Bus
System ROM
The PC uses 128 KB of 200 ns, Flash EEPROM implemented within a single
256 K X 8-bit ROM chip. This is a ROM that can be returned to its
unprogrammed state, by the application of appropriate electrical signals to
its pins, and then reprogrammed with the latest upgrade firmware.
The System ROM contains the system BIOS (including the boot code, the
ISA and PCI initialization, RPO, DMI, the Setup program and the Power-On
Self-Test routines, plus their error messages).
Refer to chapter 4, Summary of the HP/Phoenix BIOS, for more information
on the BIOS.
Other ISA Accessory Devices
ISA expansion cards (accessory boards) are for slow peripheral accessories.
For minitower models, there are four slots on the ISA bus for expansion
cards (although one of these is a combination slot with the PCI bus). For
desktop models, there are three slots on the ISA bus for expansion cards
(although one of these is a combination slot with the PCI bus).
