DevHelp_ABIOSCommonEntry

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This service starts an ABIOS common entry point according to the Advanced BIOS Transfer Convention.

Syntax

USHORT APIENTRY DevHelp_ABIOSCommonEntry (NPBYTE ReqBlk,
                                          USHORT Entry_Type)

Parameters

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 error:

ERROR_LID_DOES_NOT_EXIST (0x02)
ERROR_ABIOS_NOT_PRESENT (0x03)
ERROR_NOT_YOUR_LID (0x04)
ERROR_INVALID_ENTRY_POINT (0x05)

Remarks

ABIOSCommonEntry sets up the stack for the call to one of the Advanced BIOS common entry points. It then invokes the indicated ABIOS common entry point. On return from the ABIOS function, ABIOSCommonEntry 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 data segment of the physical device driver.

Example Code

C

Calling Sequence in C

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

USHORT APIENTRY DevHelp_ABIOSCommonEntry (NPBYTE ReqBlk,
                                          USHORT Entry_Type)

Assembler

Calling Sequence in Assembler

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_ABIOSCommonEntry

CALL  [Device_Help]

Results in Assembler

   'C' Clear if successful.
       The ABIOS common entry point 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)