source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/BootVars.asm@ 490

; Project name  :   XTIDE Universal BIOS
; Description   :   Functions for accessings BOOTVARS.

;
; XTIDE Universal BIOS and Associated Tools 
; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2012 by XTIDE Universal BIOS Team.
;
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
; 
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.      
; Visit http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
;       

; Section containing code
SECTION .text

;--------------------------------------------------------------------
; BootVars_Initialize
;   Parameters:
;       DS:     RAMVARS Segment
;       ES:     BDA Segment
;   Returns:
;       Nothing
;   Corrupts registers:
;       AX, CX, DX, DI
;--------------------------------------------------------------------
BootVars_Initialize:
%ifdef MODULE_8BIT_IDE
    mov     WORD [es:BOOTVARS.wNextXTCFportToScan], XTCF_BASE_PORT_1
%endif

    ; Clear to zero
    mov     al, DRVDETECTINFO_size
    mul     BYTE [cs:ROMVARS.bIdeCnt]
    mov     di, BOOTVARS.clearToZeroFromThisPoint   ; We must not initialize anything before this!
    add     ax, BOOTVARS_size
    sub     ax, di
    xchg    cx, ax

%ifdef MODULE_HOTKEYS
    call    Memory_ZeroESDIwithSizeInCX

    ; Store default drives to boot from
    mov     dl, [cs:ROMVARS.bBootDrv]

    ; fall through to BootVars_StoreHotkeyForDriveNumberInDL

;--------------------------------------------------------------------
; BootVars_StoreHotkeyForDriveNumberInDL
;   Parameters:
;       DL:     Floppy or Hard Drive number
;       DS:     RAMVARS Segment
;       ES:     BDA Segment
;   Returns:
;       Nothing
;   Corrupts registers:
;       AX, CX, DI
;--------------------------------------------------------------------
BootVars_StoreHotkeyForDriveNumberInDL:
    mov     WORD [es:BOOTVARS.hotkeyVars+HOTKEYVARS.wHddAndFddLetters], DEFAULT_HARD_DRIVE_LETTER | (DEFAULT_FLOPPY_DRIVE_LETTER<<8)
    call    HotkeyBar_ConvertDriveNumberFromDLtoDriveLetter
    jmp     HotkeyBar_StoreHotkeyToBootvarsForDriveLetterInDL

%else
    jmp     Memory_ZeroESDIwithSizeInCX

%endif ; MODULE_HOTKEYS


%ifdef MODULE_8BIT_IDE
;--------------------------------------------------------------------
; BootVars_GetNextXTCFportToDetectToDX
;   Parameters:
;       ES:     BDA Segment
;   Returns:
;       DX:     Next XT-CF port to detect
;   Corrupts registers:
;       AX
;--------------------------------------------------------------------
BootVars_GetNextXTCFportToDetectToDX:
    mov     dx, [es:BOOTVARS.wNextXTCFportToScan]
    test    dl, dl
    jz      SHORT .NextOneIs240hor340h
    add     WORD [es:BOOTVARS.wNextXTCFportToScan], XTCF_BASE_PORT_3 - XTCF_BASE_PORT_2
    ret
.NextOneIs240hor340h:
    mov     BYTE [es:BOOTVARS.wNextXTCFportToScan], XTCF_BASE_PORT_2 & 0FFh ; 40h
    ret     
%endif ; MODULE_8BIT_IDE