Arbor Technology EasyBoard-882E, Руководство пользователя

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Appendices
A.4. 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 (Note):
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.
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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.
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:
HIGH BYTE XY
XY The upper nibble ‘X’ indicates the function number that is being executed. ‘X’
can be from 0 to 7.
0 = func#0, disable all devices on the BUS concerned.
1 = func#1, static devices initialization on the BUS concerned.
2 = func#2, output device initialization on the BUS concerned.
3 = func#3, input device initialization on the BUS concerned.
4 = func#4, IPL device initialization on the BUS concerned.
5 = func#5, general device initialization on the BUS concerned.
6 = func#6, error reporting for the BUS concerned.
7 = func#7, add-on ROM initialization for all BUSes.
8 = func#8, BBS ROM initialization for all BUSes.
The lower nibble ‘Y’ indicates the BUS on which the different routines are being