source: xtideuniversalbios/trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH23h_HFeatures.asm@ 588

; Project name  :   XTIDE Universal BIOS
; Description   :   Int 13h function AH=23h,
;                   Set Controller Features Register.

;
; XTIDE Universal BIOS and Associated Tools
; Copyright (C) 2009-2010 by Tomi Tilli, 2011-2013 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

;--------------------------------------------------------------------
; Int 13h function AH=23h, Set Controller Features Register.
;
; AH23h_HandlerForSetControllerFeatures
;   Parameters:
;       AL, CX: Same as in INTPACK
;       DL:     Translated Drive number
;       DS:DI:  Ptr to DPT (in RAMVARS segment)
;       SS:BP:  Ptr to IDEPACK
;   Parameters on INTPACK:
;       AL:     Feature Number (parameter to Features Register = subcommand)
;   (Parameter registers are undocumented, these are specific for this BIOS):
;       BL:     Parameter to Sector Count Register (subcommand specific)
;       BH:     Parameter to LBA Low / Sector Number Register (subcommand specific)
;       CL:     Parameter to LBA Middle / Cylinder Low Register (subcommand specific)
;       CH:     Parameter to LBA High / Cylinder High Register (subcommand specific)
;   Returns with INTPACK:
;       AH:     Int 13h return status
;       CF:     0 if successful, 1 if error
;--------------------------------------------------------------------
AH23h_HandlerForSetControllerFeatures:
    xchg    si, ax      ; SI = Feature Number
    mov     dx, [bp+IDEPACK.intpack+INTPACK.bx]
%ifndef USE_186
    call    AH23h_SetControllerFeatures
    jmp     Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
%else
    push    Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
    ; Fall to AH23h_SetControllerFeatures
%endif


;--------------------------------------------------------------------
; AH23h_SetControllerFeatures
;   Parameters:
;       DL:     Parameter to Sector Count Register (subcommand specific)
;       DH:     Parameter to LBA Low / Sector Number Register (subcommand specific)
;       CL:     Parameter to LBA Middle / Cylinder Low Register (subcommand specific)
;       CH:     Parameter to LBA High / Cylinder High Register (subcommand specific)
;       SI:     Feature Number (parameter to Features Register = subcommand)
;       DS:DI:  Ptr to DPT (in RAMVARS segment)
;       SS:BP:  Ptr to IDEPACK
;   Returns:
;       AH:     Int 13h return status
;       CF:     0 if successful, 1 if error
;   Corrupts registers:
;       AL, BX, CX, DX
;--------------------------------------------------------------------
AH23h_SetControllerFeatures:
    mov     al, COMMAND_SET_FEATURES
    mov     bx, TIMEOUT_AND_STATUS_TO_WAIT(TIMEOUT_BSY, FLG_STATUS_BSY)
    jmp     Idepack_StoreNonExtParametersAndIssueCommandFromAL


;--------------------------------------------------------------------
; AH23h_Enable8bitPioMode
; AH23h_Disable8bitPioMode
;   Parameters:
;       DS:DI:  Ptr to DPT (in RAMVARS segment)
;       SS:BP:  Ptr to IDEPACK
;   Returns:
;       AH:     Int 13h return status
;       CF:     0 if successful, 1 if error
;   Corrupts registers:
;       AL, BX, CX, DX, SI
;--------------------------------------------------------------------
%ifdef MODULE_8BIT_IDE
AH23h_Enable8bitPioMode:
    mov     si, FEATURE_ENABLE_8BIT_PIO_TRANSFER_MODE
    jmp     SHORT AH23h_SetControllerFeatures
AH23h_Disable8bitPioMode:
    mov     si, FEATURE_DISABLE_8BIT_PIO_TRANSFER_MODE
    call    AH23h_SetControllerFeatures
    xor     ah, ah          ; Clear error since modern drives might not understand the command and are
    ret                     ; always in 16-bit mode anyway
%endif