kernel/kernel/dosidle.asm

97 lines
2.8 KiB
NASM

; File:
; DosIdle.asm
; Description:
; Dos Idle Interrupt Call
;
; DOS-C
; Copyright (c) 1995, 1999
; James B. Tabor
; All Rights Reserved
;
; This file is part of DOS-C.
;
; DOS-C 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, or (at your option) any later version.
;
; DOS-C 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.
;
; You should have received a copy of the GNU General Public
; License along with DOS-C; see the file COPYING. If not,
; write to the Free Software Foundation, 675 Mass Ave,
; Cambridge, MA 02139, USA.
;
;
%include "segs.inc"
PSP_USERSP equ 2eh
PSP_USERSS equ 30h
segment HMA_TEXT
global _DosIdle_int
global _DosIdle_hlt
extern _InDOS
extern _cu_psp
extern _MachineId
extern critical_sp
extern _user_r
; variables as the following are "part of" module inthndlr.c
; because of the define MAIN before include globals.h there!
extern _HaltCpuWhileIdle
extern _DGROUP_
;
_DosIdle_hlt:
push ds
mov ds, [cs:_DGROUP_]
cmp byte [_HaltCpuWhileIdle],1
jb DosId0
pushf
sti
hlt ; save some energy :-)
popf
DosId0: pop ds
retn
;
_DosIdle_int:
call _DosIdle_hlt
push ds
mov ds, [cs:_DGROUP_]
cmp byte [_InDOS],1
ja DosId1
call Do_DosI
DosId1:
pop ds
retn
Do_DosI:
push ax
push es
push word [_MachineId]
push word [_user_r]
push word [_user_r+2]
mov es,word [_cu_psp]
push word [es:PSP_USERSS]
push word [es:PSP_USERSP]
int 28h
mov es,word [_cu_psp]
pop word [es:PSP_USERSP]
pop word [es:PSP_USERSS]
pop word [_user_r+2]
pop word [_user_r]
pop word [_MachineId]
pop es
pop ax
ret
; segment _DATA ; belongs to DGROUP
; whatever db whatever