The X-Philes (2nd Revision)/The X-Philes Number 1 (1995).iso/xphiles/hp95/freyja_t.z/freyja_t/libasm.asm

Assembly Source File | 1992-04-14 | 9KB | 605 lines

; LIBASM.ASM -- Assembly Language DOS Interface Routines
;    Turbo C/ANSI Version, assumes Small model (64K code, separate 64K data)
;    Written April 1991 by Craig A. Finseth

; -------------------- Constants and Macros --------------------

TRUE    equ    255
FALSE    equ    0
NUL    equ    0
BEL    equ    7
CR    equ    13
LF    equ    10
SPACE    equ    32

; C function call stack layout -- SI, DI, BP, and SP must be preserved

old_bp    equ    0
ret_addr equ    2
arg1    equ    4
arg2    equ    6
arg3    equ    8
arg4    equ    10
arg5    equ    12
arg6    equ    14
arg7    equ    16
arg8    equ    18

; "safe" stack layout -- BP is not saved

sret_addr equ    0
sarg1    equ    2
sarg2    equ    4
sarg3    equ    6
sarg4    equ    8
sarg5    equ    10
sarg6    equ    12
sarg7    equ    14
sarg8    equ    16

clear    macro    x
    xor        x,x
    endm

zero    macro    x
    xor        x,x
    endm

testz    macro    x
    or        x,x
    endm

; -------------------- Data Segment --------------------

_DATA    segment    word public 'DATA'    ; initialized data

    extrn    _t_attrib : byte    ; video attribute to use

iscolor    db    FALSE
wastext    db    TRUE
_DATA    ends

_BSS    segment    word public 'BSS'        ; uninitialized data
oldmode    db    ?
cursor_def dw    ?
_BSS    ends

DGROUP    group    _DATA, _BSS
    assume    ds:DGROUP

; -------------------- Code Segment --------------------

_TEXT    segment    byte public 'CODE'
    assume    cs:_TEXT

    public    _BlockAlloc, _BlockFree, _BlockGet, _BlockPut
    public    _c_service
    public    _JFiniA, _JInitA, _JGetKeyA, _JIsKeyA, _JLightOff, _JLightOn,
    public    _JPushKeyA
    public    _lseeka, _PSystem
    public    _VidInit, _VidFini, _VidBell, _VidChar, _VidClear, _VidCursor
    public    _VidCurOff, _VidCurOn

; ------------------------------------------------------------

; Allocate a block of memory and return the starting paragraph number
; or zero.

;    unsigned
;    BlockAlloc(unsigned para)
;    C Callable

_BlockAlloc proc near
    mov    BX,SP
    mov    BX,[BX] + sarg1
    mov    AH,48H
    clc
    int    21H
    jc    alloc_no
    ret
alloc_no: zero    AX
    ret
_BlockAlloc endp


; ------------------------------------------------------------

; Free a block of memory.

;    void
;    BlockFree(unsigned para)
;    C Callable

_BlockFree proc    near
    mov    BX,SP
    mov    BX,[BX] + sarg1
    push    ES
    mov    ES,BX
    mov    AH,49H
    int    21H
    pop    ES
    ret
_BlockFree endp


; ------------------------------------------------------------

; Get a block of data from high memory.

;    void
;    BlockGet(char *to, char huge *from, int len)
;    C Callable

;    do    {
;        *to++ = *from++;
;        } while (--len > 0);

_BlockGet proc    near
    push    BP
    mov    BP,SP
    push    DI
    push    SI
    push    DS
    push    ES

    mov    DI,[BP] + arg1        ; to
    mov    AX,DS            ;  & segment
    mov    ES,AX

    mov    SI,[BP] + arg2        ; from
    mov    AX,[BP] + arg3        ;  & segment
    mov    DS,AX

    mov    CX,[BP] + arg4        ; CX is len
    cld

;mloop:    mov    AL,DS:[SI]        ; *from++
;    inc    SI
;    mov    ES:[DI],AL        ; *to++ =
;    inc    DI
;    loop    mloop            ; while --len>0

    rep    movsb

    pop    ES
    pop    DS
    pop    SI
    pop    DI
    pop    BP
    ret
_BlockGet endp


; ------------------------------------------------------------

; Put a block of data into high memory.

;    void
;    BlockPut(char huge *to, char *from, int len)
;    C Callable

;    do    {
;        *to++ = *from++;
;        } while (--len > 0);

_BlockPut proc    near
    push    BP
    mov    BP,SP
    push    DI
    push    SI
    push    ES

    mov    DI,[BP] + arg1        ; to
    mov    AX,[BP] + arg2        ;  & segment
    mov    ES,AX

    mov    SI,[BP] + arg3        ; from

    mov    CX,[BP] + arg4        ; CX is len
    cld

;mloop:    mov    AL,DS:[SI]        ; *from++
;    inc    SI
;    mov    ES:[DI],AL        ; *to++ =
;    inc    DI
;    loop    mloop            ; while --len>0

    rep    movsb

    pop    ES
    pop    SI
    pop    DI
    pop    BP
    ret
_BlockPut endp


; ------------------------------------------------------------

; Link to Jaguar special services.

_c_service proc near
    push    BP
    mov    BP,SP
    xchg    DI,[BP+4]
    pop    BP
    int    60H
    ret
_c_service endp


; ------------------------------------------------------------

; Terminate any special HP95LX processing.

;    void
;    JFiniA(void)
;    C Callable

_JFiniA    proc    near
    mov    AH,4AH        ; turn on serial port power
    mov    AL,1
    int    15H
    ret
_JFiniA    endp


; ------------------------------------------------------------

; Initialize any special HP95LX processing.

;    void
;    JInitA(void)
;    C Callable

_JInitA    proc    near
    mov    AH,4AH        ; turn off serial port power
    zero    AL
    int    15H
    ret
_JInitA    endp


; ------------------------------------------------------------

; Return the next key.  HP95LX specific.

;    int
;    JGetKeyA(void)
;    C Callable

_JGetKeyA proc    near
    mov    AH,10H
    int    16H
    ret
_JGetKeyA endp


; ------------------------------------------------------------

; Return non-zero if a key is available or zero if not.  HP95LX specific.

;    int
;    JIsKeyA(void)
;    C Callable

_JIsKeyA proc    near
    mov    AH,11H
    int    16H
    jz    jik_none
    mov    AX,1
    ret
jik_none: zero    AX
    ret
_JIsKeyA endp


; ------------------------------------------------------------

; Turn off the light sleep mode when checking the key press status.
; HP95LX specific.

;    void
;    JLightOff(void)
;    C Callable

_JLightOff proc    near
    mov    AX,4E00H
    int    15H
    ret
_JLightOff endp


; ------------------------------------------------------------

; Turn on the light sleep mode when checking the key press status.
; HP95LX specific.

;    void
;    JLightOn(void)
;    C Callable

_JLightOn proc    near
    mov    AX,4E01H
    int    15H
    ret
_JLightOn endp


; ------------------------------------------------------------

; Push the specified key into the input buffer.  HP95LX specific.

;    void
;    JPushKeyA(int key)
;    C Callable

_JPushKeyA proc    near
    push    BP
    mov    BP,SP
    mov    CX,[BP] + arg1
    mov    AH,05H
    int    16H
    pop    BP
    ret
_JPushKeyA endp


; ------------------------------------------------------------

;    long
;    lseeka(int fd, long dist, int mode)
;    C callable

_lseeka    proc        near
        mov        BX,SP
        mov        DX,[BX] + sarg2
        mov        CX,[BX] + sarg3
        mov        AX,[BX] + sarg4
        mov        AH,42H
        mov        BX,[BX] + sarg1
        int        21H
        jnc        lseek_a
        mov        DX,-1
        neg        AX
lseek_a:    ret
_lseeka    endp


; ------------------------------------------------------------

;    int
;    PSystem(int AH, ...) /* int DX, int CX, int BX, int AL, int SI, int DI */
;    C callable
;    Note:  if the carry flag is set, the return code is negated

_PSystem proc    near
    push    BP
    mov    BP,SP
    push    DI
    push    SI

    mov    AX,[BP] + arg5        ; AL
    mov    BX,[BP] + arg1        ; AH
    mov    AH,BL
    mov    DX,[BP] + arg2
    mov    CX,[BP] + arg3
    mov    BX,[BP] + arg4
    mov    SI,[BP] + arg6
    mov    DI,[BP] + arg7

    clc
    int    21H
    jnc    psyst_ok
    neg    AX
    pop    SI
    pop    DI
    pop    BP
    ret

psyst_ok: and    AX,7FFFH
    pop    SI
    pop    DI
    pop    BP
    ret
_PSystem endp


; ------------------------------------------------------------

; Initialize the screen to 80x25 text mode.  Used (needed) for direct
; memory output only.

;    int
;    VidInit(void)
;    C callable

_VidInit proc    near
    int    11H            ; equipment check
    and    AL,30H
    cmp    AL,30H
    jz    vidi_mret        ; monochome display

    mov    iscolor,TRUE

    mov    AH,0FH        ; get current video mode
    int    10H
    cmp    AL,2            ; 80x25 BW
    jz    vidi_cret
    cmp    AL,3            ; 80x25 color
    jz    vidi_cret

    mov    oldmode,AL    ; save old mode
    mov    wastext,FALSE
    mov    AX,0002H        ; set to mode 2, 80x25 BW
    int    10H

vidi_cret:
    mov    CX,0007H
    mov    cursor_def,CX

    mov    AX,0B800H    ; color base
    ret

vidi_mret:
    mov    CX,000CH
    mov    cursor_def,CX

    mov    AX,0B000H    ; monochrome base
    ret
_VidInit endp


; ------------------------------------------------------------

; Restore the screen.  Used (needed) for direct memory output only.

;    void
;    VidFini(void)
;    C callable

_VidFini proc    near
    test    iscolor,0FFH
    jz    vidf_ret
    test    wastext,0FFH
    jnz    vidf_ret

    mov    AH,0            ; put old mode back
    mov    AL,oldmode
    int    10H
vidf_ret: ret
_VidFini endp


; ------------------------------------------------------------

; Ring the bell.  Usable for both BIOS and direct memory output.

;    void
;    VidBell(void)
;    C callable

_VidBell proc    near
    mov    AL,BEL
    zero    BL
    mov    AH,14        ; write TTY
    int    10H
    ret
_VidBell endp


; ------------------------------------------------------------

; Write the specified character to the current cursor location.
; Usable for BIOS output only.

;    void
;    VidChar(char char)
;    C callable

_VidChar proc    near
    push    BP
    mov    BP,SP

    mov    AL,[BP] + arg1
    zero    BH            ; page
    mov    BL,_t_attrib
    mov    CX,1            ; repeat count

    mov    AH,9            ; write char and attribute
    int    10H
    pop    BP
    ret
_VidChar endp


; ------------------------------------------------------------

; Clear the next COUNT characters.  Usable for BIOS output only.

;    void
;    VidClear(int count)
;    C callable

_VidClear proc    near
    push    BP
    mov    BP,SP

    mov    AL,SPACE
    zero    BH            ; page
    mov    BL,_t_attrib
    mov    CX,[BP] + arg1        ; repeat count: # of char to clear
    test    CX,0FFFFH
    jz    vidc_ret

    mov    AH,9            ; write char and attribute
    int    10H
vidc_ret:
    pop    BP
    ret
_VidClear endp


; ------------------------------------------------------------

; Set the cursor to the specified row/column.  Usable for both BIOS
; and direct memory output.

;    void
;    VidCursor(int row, int col)
;    C callable

_VidCursor proc    near
    push    BP
    mov    BP,SP

    mov    CL,[BP] + arg1
    mov    DL,[BP] + arg2        ; col
    mov    DH,CL            ; row

    zero    BH            ; page
    mov    AH,2            ; set cursor position
    int    10H
    pop    BP
    ret
_VidCursor endp


; ------------------------------------------------------------

; Tur the cursor off.

;    void
;    VidCurOff(void)
;    C callable

_VidCurOff proc near
    mov    AH,1        ; set cursor size
    mov    CX,0FF00H
    int    10H
    ret
_VidCurOff endp


; ------------------------------------------------------------

; Set the cursor to a block cursor.

;    void
;    VidCurOn(void)
;    C callable

_VidCurOn proc near
    mov    AH,1        ; set cursor size
    mov    CX,cursor_def
    int    10H
    ret
_VidCurOn endp


_TEXT    ends

        end

; end of LIBASM.ASM -- Assembly Language DOS Interface Routines