IBM 560E manual Calling Convention, Parameter Structure, Input Field

Calling Convention

The

client can invoke the SMAPI

BIOS

with

a far-call to the entry

point

that is specified in the header

file. All

parameters

for

the

BIOS

and

other

results

are

stored

in

the client data

area;

the client

needs

to prepare an input parameter / output

parameter area in its data

area, and informs

this

area

by

pushing

those pointers

onto

the

its

stack before the far-calls.

The

SMAPI

BIOS

uses

the

stack/data

area

directly

with

the

selector

when

the BIOS is invoked. Therefore, the

caller needs

to

define

the

same

privilege

level

as

the BIOS.

Parameter Structure

The	memory			allocation		for the input/output field should				be	prepared
by	the		caller. The			input field specifies the function				request to the
SMAPI		BIOS,		and	the	BIOS fills in the		return value to		the	output
field.
Input Field
Field							Offset		Length
Major		Function		Number			00h		Byte
Minor		Function		Number			01h		Byte
Parameter			1				02h		Word
Parameter			2				04h		Word
Parameter			3				06h		Word
Parameter			4				08h		Dword
Parameter			5				0Ch		Dword
Output Field
Field							Offset		Length
Return Code							00h		Byte
Auxiliary			Return Code				01h		Byte
Parameter			1				02h		Word
Parameter			2				04h		Word
Parameter			3				06h		Word
Parameter			4				08h		Dword
Parameter			5				0Ch		Dword
A-6	ThinkPad			560/560E	SMAPI	BIOS