Lpc Interface - Micros Systems Workstation 5 Service Manual

Workstation 5 System Board Technical Descriptions

LPC Interface

LPC Interface

The Low Pin Count Interface is a PCI like-bus comprised of seven signals lines
and is used to replace the legacy ISA bus as the interface between the
Companion Device and Super IO and BIOS devices. Figure 2-9 below displays
a block diagram of the LPC Bus as implemented on the Workstation 5 System
Board.
A total of three devices and the LPC Debug slot are attached to the LPC Bus.
Because the LPC Bus is a replacement for the legacy for the ISA Bus, the
BIOS redirects Port 80H POST Codes to the LPC Bus.
Two lines from the Companion Device, BOS0 and BOS1 specify location of
the Boot Device after a hardware reset. These pins are configured to 'Boot
from a Memory Device on the LPC Bus,' in this case BIOS EEPROM U36.
2-20
Figure 2-9: LPC Bus Block Diagram
Workstation 5 Field Service Guide