DevHelp ABIOSCall

This service starts an ABIOS function for the Operating System Transfer Convention.

Syntax

USHORT APIENTRY DevHelp_ABIOSCall (USHORT Lid,
                                   NPBYTE ReqBlk,
                                   USHORT Entry_Type)

Parameters

Lid (USHORT) - input

Logical ID

ReqBlk (NPBYTE) - input

Offset in data segment to ABIOS request block

Entry_Type (USHORT) - input

Specifies entry point

ABIOS_EP_START start

ABIOS_EP_INTERRUPT interrupt

ABIOS_EP_TIMEOUT timeout

Return Code

Success indicator: 0

Possible errors:

ERROR_LID_DOES_NOT_EXIST (0x02)

ERROR_ABIOS_NOT_PRESENT (0x03)

ERROR_NOT_YOUR_LID (0x04)

ERROR_INVALID_ENTRY_POINT (0x05)

Remarks

ABIOSCall sets up the stack for the call to ABIOS. The indicated ABIOS function is called according to the Operating System Transfer Convention. When the ABIOS function returns, ABIOSCall cleans up the stack before returning to the physical device driver.

The DS register must point to the physical device driver's data segment. If the DS register was used in a previous call to PhysToVirt, it must be reset to the device driver's data segment.

Example Code

C

Calling Sequence in C

#include  "abios.h"
#include  "dhcalls.h"

USHORT APIENTRY DevHelp_ABIOSCall (USHORT Lid,
                                   NPBYTE ReqBlk,
                                   USHORT Entry_Type)

Assembler

Calling Sequence in Assembler

MOV   AX,LID              ; Logical ID
MOV   SI,RB_Offset        ; Offset in data segment to ABIOS request block
MOV   DH,Entry_Point      ; Specifies entry point
                          ; 0 = start
                          ; 1 = interrupt
                          ; 2 = timeout
MOV   DL,DevHlp_ABIOSCall

CALL  [Device_Help]

Results in Assembler

   'C' Clear if successful.
       The ABIOS service is invoked.

   'C' Set if error.
       AX = Error code.
            Possible errors:
               ERROR_LID_DOES_NOT_EXIST              (0x02)
               ERROR_ABIOS_NOT_PRESENT               (0x03)
               ERROR_NOT_YOUR_LID                    (0x04)
               ERROR_INVALID_ENTRY_POINT             (0x05)