ADLINK Express-LPC - Manual (Page 78)

Express-LPC User’s Manual Page 78
9.4 OEM POST Error Checkpoints
Checkpoints from the range 61h to 70h are reserved for chipset vendors & system
manufacturers. The error associated with this value may be different from one platform to the next.
9.5 DIM Code Checkpoints
The Device Initialization Manager (DIM) gets control at various times during BIOS POST to
initialize different system busses. The following table describes the main checkpoints where the
DIM module is accessed:
While control is in the different functions, additional checkpoints are output to port 80h as a
word value to identify the routines under execution. The low byte value indicates the main
POST Code Checkpoint. The high byte is divided into two nibbles and contains two fields. The
details of the high byte of these checkpoints are as follows:
Checkpoints may differ between different platforms based on system configuration.
Checkpoints may change due to vendor requirements, system chipset or option ROMs
from add-in PCI devices.
Checkpoint Description
2A Initialize different buses and perform the following functions: Reset, Detect, and Disable
(function 0); Static Device Initialization (function 1); Boot Output Device Initialization (function 2).
Function 0 disables all device nodes, PCI devices, and PnP ISA cards. It also assigns PCI bus
numbers. Function 1 initializes all static devices that include manual configured onboard
peripherals, memory and I/O decode windows in PCI- PCI bridges, and noncompliant PCI
devices. Static resources are also reserved. Function 2 searches for and initializes any PnP,
PCI, or AGP video devices.
38 Initialize different buses and perform the following functions: Boot Input Device Initialization
(function 3); IPL Device Initialization (function 4); General Device Initialization (function 5).
Function 3 searches for and configures PCI input devices and detects if system has standard
keyboard controller. Function 4 searches for and configures all PnP and PCI boot devices.
Function 5 configures all onboard peripherals that are set to an automatic configuration and
configures all remaining PnP and PCI devices.