; MS-DOS Kermit system-dependent module for the Wang PC
; Jeff Damens, CUCCA
; Add global entry point vtstat for use by Status in mssset.
; Correct corruption of registers in GETBAUD, CLRBUF, and POSCUR.
; Add clearing of terminal emulation flag, flags.vtflg, in procedure lclini.
; Joe R. Doupnik 12 March 1986

        public  serini, serrst, clrbuf, outchr, coms, vts, vtstat, dodel, ctlu
        public  cmblnk, locate, lclini, prtchr, dobaud, clearl
        public  dodisk, getbaud, beep, term, puthlp
        public  count, poscur, machnam, sendbr, putmod, clrmod
        public  setktab, setkhlp, xofsnt, showkey
        include mssdef.h

false   equ     0
true    equ     1

ctrla   equ     1               ; Control-A.

auxin   equ     3
auxout  equ     4
auxfil  equ     3               ; file number of aux file.
iordy   equ     6               ; input ready function
write   equ     40h
wbios   equ     88h
settrp  equ     02h
clrtrp  equ     03h
chrrdy  equ     01h
txrdy   equ     02h

rcvdat  equ     1080h
rcvstat equ     1082h
rcvmod  equ     1084h
rcvcmd  equ     1086h
trdat   equ     1088h
trmod   equ     108ch
wrcmd   equ     108eh

; mode bits
mod1    equ     4dh                     ; clock rate, 8 bits, 1 stop bit
mod2    equ     30h                     ; internal clock

; command register bits
txen    equ     01h
dtr     equ     02h
rxen    equ     04h
brk     equ     08h
clrerr  equ     10h
rts     equ     20h


datas   segment public 'datas'
        extrn   drives:byte, flags:byte, trans:byte
        extrn   portval:word, port1:byte, port2:byte

portin  db      0
crlf    db      cr,lf,'$'
machnam db      'FIELD TEST Wang$'
noimp   db      cr,lf,'Command not implemented.$'
shkmsg  db      'Not implemented.'
shklen  equ     $-shkmsg
xofsnt  db      0               ; Say if we sent an XOFF.
xofrcv  db      0               ; Say if we received an XOFF.
setktab db      0
setkhlp db      0
invseq  db      esc,'[7m$'      ; Reverse video on.
nrmseq  db      esc,'[0m$'      ; Reverse video off.
ivlseq  db      79 dup (' '),cr,'$'     ; Make a line inverse video
comphlp db      cr,lf,'1 (COM1)   2 (COM2)$'
delstr  db      BS,' ',BS,'$'   ; Delete string.
clrlin  db      cr,esc,'[K$'
tmp     db      ?,'$'
temp    dw      0
temp1   dw      ?               ; Temporary storage.
temp2   dw      ?               ; Temporary storage.

; Entries for choosing communications port. [19b]
comptab db      04H
        db      01H,'1$'
        dw      01H
        db      01H,'2$'
        dw      00H
        db      04H,'COM1$'
        dw      01H
        db      04H,'COM2$'
        dw      00H

; variables for serial interrupt handler

source  db      bufsiz DUP(?)   ; Buffer for data from port.
bufout  dw      0               ; buffer removal ptr
count   dw      0               ; Number of chars in int buffer.
bufin   dw      0               ; buffer insertion ptr
telflg  db      0               ; Are we acting as a terminal. [16] [17c]
clreol  db      esc,'[0K$'
blank   db      esc,'[H',esc,'[J$'
movcur  db      esc,'['
colno   db      20 dup (?)
ten     db      10
prthnd  dw      0
ourarg  termarg <>
; must parallel baud rate defs in pcdefs.
baudtab db      0ffh            ; 45.5 baud (not supported)
        db      0               ; 50
        db      1               ; 75
        db      2               ; 110
        db      3               ; 134.5
        db      4               ; 150
        db      5               ; 300
        db      6               ; 600
        db      7               ; 1200
        db      8               ; 1800
        db      9               ; 2000
        db      10              ; 2400
        db      12              ; 4800
        db      14              ; 9600
        db      15              ; 19.2k
        db      0ffh            ; 38.4k (ha)

nbaud   equ     $-baudtab
qid     dw      ?
prtcnt  dw      ?
trqid   dw      ?
tmqid   dw      ?
brflg   db      ?
datas   ends

code    segment public
        extrn   comnd:near, dopar:near, prserr:near
        assume  cs:code,ds:datas

DODISK  PROC    NEAR
        mov ah,gcurdsk                  ; Current disk value to AL.
        int dos
        mov dl,al                       ; Put current disk in DL.
        mov ah,seldsk                   ; Select current disk.
        int dos                         ; Get number of drives in AL.
        mov drives,al
        ret
DODISK  ENDP

; Clear the input buffer before sending a packet. [20e]

CLRBUF  PROC    NEAR
        push    ax              ; save regs [jrd]
        push    bx              ; [jrd]
clrb2:  mov     ah,ioctl        ; [jrd]
        mov     bx,auxfil
        mov     al,iordy
        int     dos
        cmp     al,0ffh
        jne     clrb1                   ; not ready, keep going
        mov     ah,auxin
        int     dos
;;;[jrd]        jmp     clrbuf                  ; read char and keep going.
        jmp     clrb2           ; [jrd]
clrb1:  mov     count,0
        mov ax,offset source
        mov bufin,ax
        mov bufout,ax
        pop     bx              ; restore regs [jrd]
        pop     ax              ; [jrd]
        ret
CLRBUF  ENDP

; Common routine to clear to end-of-line. [19a]

CLEARL  PROC    NEAR
        mov dx,offset clreol
        mov ah,prstr
        int dos
        ret
CLEARL  ENDP

; This routine should set the baud rate for the current port but it
; is actually done in SERINI.
dobaud  proc    near
        ret
dobaud  endp

; Send a break out the current serial port.  Returns normally.
sendbr: push dx
        push ax
        push cx
        push ds                 ; preserve data segment
        mov ax,cs
        mov ds,ax               ; handler is in code segment
        mov al,settrp
        mov bx,txrdy            ; interrupt on transmitter empty
        mov cx,0                ; interrupt immediately
        mov dx,offset sendb1    ; handler routine
        int wbios
        pop ds
        mov trqid,bx
        push ds
        mov ax,cs
        mov ds,ax
        mov al,settrp
        mov bx,0                ; 10 ms timer
        mov cx,21               ; after 21 times - approx 200 ms.
        mov dx,offset sendb2    ; timer interrupt
        int wbios
        pop ds
        mov tmqid,bx

        mov brflg,1
        mov dx,rcvcmd
        in al,dx                ; Read command register.
        or al,brk+txen          ; Set send-break bit.
        mov dx,wrcmd            ; Write command register.
        out dx,al
pause:  cmp brflg,0
        jne pause               ; while non-zero, keep going
        mov al,clrtrp           ; clear the trap
        mov bx,trqid
        int wbios
        mov al,clrtrp
        mov bx,tmqid
        int wbios
        pop cx
        pop ax
        pop dx
        ret

sendb1  proc    far
        ret
sendb1  endp

sendb2  proc    far
        push ax
        push ds
        mov ax,seg datas
        mov ds,ax
        mov brflg,0
        mov dx,rcvcmd
        in al,dx
        and al,not (txen + brk)
        mov dx,wrcmd
        out dx,al
        pop ds
        pop ax
        ret
sendb2  endp


; Write a line in inverse video at the bottom of the screen...
; the line is passed in dx, terminated by a $.  Returns normally.
putmod  proc    near
        push    dx              ; preserve message
        mov     dx,24 * 100H    ; line 24
        call    poscur
        mov     dx,offset invseq ; put into inverse video
        mov     ah,prstr
        int     dos
        pop     dx
        int     dos
        mov     dx,offset nrmseq ; normal videw
        int     dos
        ret                     ; and return
putmod  endp

; Clear the mode line written by putmod.  Returns normally.
clrmod  proc    near
        mov     dx,24 * 100H
        call    poscur
        call    clearl
        ret
clrmod  endp

; Put a help message one the screen in reverse video.  Pass
; the message in AX, terminated by a null.  Returns normally.
; The message is put wherever the cursor currently is located.
puthlp  proc    near
        push ax
        mov ah,prstr            ; Leave some room before the message.
        mov dx,offset crlf
        int dos
        mov dx,offset invseq    ; Put into reverse video.
        int dos
        pop si                  ; Put message address here.
puth0:  mov ah,prstr
        mov dx,offset ivlseq    ; Make line inverse video
        int dos
puth1:  lodsb
        cmp al,0                ; Terminated with a null.
        je puth2
        mov dl,al
        mov ah,conout
        int dos
        cmp al,lf               ; Line feed?
        je puth0                ; Yes, clear the next line.
        jmp puth1               ; Else, just keep on writing.
puth2:  mov dx,offset nrmseq    ; Normal video.
        mov ah,prstr
        int dos
        mov dx,offset crlf
        int dos
        ret
puthlp  endp

outchr: push dx                 ; Save register.
        mov al,ah
        call dopar
        mov dl,al
        mov ah,auxout
        int dos
        pop     dx
        jmp rskp


; This routine blanks the screen.

CMBLNK  PROC    NEAR
        mov ah,prstr
        mov dx,offset blank
        int dos
        ret
CMBLNK  ENDP

LOCATE  PROC    NEAR
        mov dx,0                ; Go to top left corner of screen.
        jmp poscur              ; callret...
LOCATE  ENDP

GETBAUD PROC    NEAR
        push    ax              ; save regs [jrd]
        push    bx              ; [jrd]
        push    cx              ; [jrd]
        push    dx              ; [jrd]
        push    di              ; [jrd]
        push    es              ; [jrd]
        cld
        mov dx,rcvmod
        in al,dx
        in al,dx                ; get second mode word
        and     al,0fh          ; isolate baud rate
        mov cx,nbaud
        mov di,offset baudtab
        mov bx,ds
        mov es,bx               ; address correct segment
        mov bx,portval
        repne scasb             ; look for baud rate
        jne getb1               ; mystery baud rate...
        sub di,offset baudtab + 1
        mov [bx].baud,di        ; store baud rate in comm area
        jmp getb2       ; [jrd]
;;;[jrd]        ret                     ; and return
getb1:  mov [bx].baud,-1        ; unknown baud rate
getb2:  pop     es      ; restore regs. [jrd]
        pop     di      ; [jrd]
        pop     dx      ; [jrd]
        pop     cx      ; [jrd]
        pop     bx      ; [jrd]
        pop     ax      ; [jrd]
        ret
GETBAUD ENDP

; skip returns if no character available at port,
; otherwise returns with char in al, # of chars in buffer in dx.
PRTCHR  PROC    NEAR
prtchx: cmp count,0
        je prtch4               ; empty buffer, forget it.
        mov si,bufout
        lodsb
        cmp si,offset source + bufsiz
        jb prtch1
        mov si,offset source
prtch1: mov bufout,si
        dec count
        push bx
        mov bx,portval
        cmp [bx].parflg,PARNON ; no parity?
        je prtch3               ; then don't strip
        and al,7fh              ; else turn off parity
prtch3: mov dx,count            ; chars left in buffer
        pop bx
        ret
prtch4: jmp rskp                ; no chars...
PRTCHR  ENDP

; Position the cursor according to contents of DX.

POSCUR  PROC    NEAR
        push    es              ; save regs. [jrd]
        push    ax              ; [jrd]
        push    dx              ; [jrd]
        push    di              ; [jrd]
        mov     ax,ds
        mov     es,ax                   ; address data segment!!!
        cld
        mov     di,offset colno
        mov     al,dh                   ; row
        inc     al
        call    nout
        mov     al,';'
        stosb
        mov     al,dl                   ; col
        inc     al
        call    nout
        mov     al,'H'
        stosb
        mov     al,'$'
        stosb
        mov     dx,offset movcur
        mov     ah,prstr
        int     dos                     ; print the sequence
        pop     di              ; restore regs [jrd]
        pop     dx              ; [jrd]
        pop     ax              ; [jrd]
        pop     es              ; [jrd]
        ret
POSCUR  ENDP

NOUT    PROC    NEAR
        cbw                     ; extend to word
        div     byte ptr ten    ; divide by 10
        or      al,al           ; any quotient?
        jz      nout1           ; no, forget this
        push    ax              ; save current result
        call    nout            ; output high order
        pop     ax              ; restore
nout1:  mov     al,ah           ; get digit
        add     al,'0'          ; make printable
        stosb
        ret                     ; put in buffer and return
NOUT    endp

; Perform a delete.

DODEL   PROC    NEAR
        mov ah,prstr
        mov dx,offset delstr    ; Erase weird character.
        int dos
        ret
DODEL   ENDP

; Perform a Control-U.

CTLU    PROC    NEAR
        mov ah,prstr
        mov dx,offset clrlin
        int dos
        ret
CTLU    ENDP

COMS    PROC    NEAR
        mov dx,offset comptab
        mov bx,offset comphlp
        mov ah,cmkey
        call comnd
         jmp r
        push bx
        mov ah,cmcfm
        call comnd              ; Get a confirm.
         jmp comx               ;  Didn't get a confirm.
         nop
        pop bx
        mov flags.comflg,bl     ; Set the comm port flag.
        cmp flags.comflg,1      ; Using Com 1?
        jne coms0               ; Nope.
        mov ax,offset port1
        mov portval,ax
        ret
coms0:  mov ax,offset port2
        mov portval,ax
        ret
comx:   pop bx
        ret
COMS    ENDP

VTS     PROC    NEAR
        jmp notimp
VTS     ENDP

VTSTAT  PROC    NEAR    ; For Status display [jrd]
        ret             ; no emulator status to display
VTSTAT  ENDP

notimp: mov ah,prstr
        mov dx,offset noimp
        int dos
        jmp prserr

lclini: mov trans.escchr,ctrla  ; Use Control-A as escape char.
        mov flags.vtflg,0       ; no terminal emulation. [jrd]
        ret

showkey:
        mov ax,offset shkmsg
        mov cx,shklen
        ret


;     Common initialization for using serial port.

SERINI  PROC    NEAR
        cmp portin,0            ; already inited?
        jne serin1              ; yes, skip it
        mov portin,1            ; remember inited
        mov dx,rcvcmd
        in al,dx                ; read cmd register to reset mode ptr.
        mov dx,trmod
        mov al,mod1
        out dx,al
        push bx
        mov bx,portval
        mov si,[bx].baud
        pop bx
        mov al,baudtab[si]
        or al,mod2
        out dx,al
        mov dx,wrcmd
        mov al,txen+dtr+rxen+clrerr+rts
        out dx,al               ; enable transmit and receive
        call clrbuf             ; empty buffer
        mov al,settrp
        mov bx,chrrdy           ; interrupt on character ready
        mov cx,0                ; interrupt immediately
        mov dx,offset serint    ; handler routine
        mov prtcnt,0            ; no characters in yet
        push ds
        mov si,cs
        mov ds,si
        int wbios
        pop ds
        or al,al
        jne serin1
        mov qid,bx              ; preserve trap identification
serin1: ret                     ; We're done. [21c]
SERINI  ENDP

SERRST  PROC    NEAR
        cmp portin,0            ; already de-inited?
        je serrs1               ; yes, skip this
        mov portin,0
        mov al,clrtrp
        mov bx,qid
        int wbios
serrs1: ret
SERRST  ENDP

; serial interrupt handler
serint  proc    far
        push ds
        push ax
        push dx
        push di
        mov ax,seg datas
        mov ds,ax
        mov di,bufin
        mov dx,rcvdat
        in al,dx
        mov [di],al
        inc di
        cmp di,offset source + bufsiz
        jb sernt1
        mov di,offset source
sernt1: mov bufin,di
        inc count
        pop di
        pop dx
        pop ax
        pop ds
        ret
serint  endp


; Generate a short beep.

BEEP    PROC    NEAR
        mov dl,bell
        mov ah,conout
        int dos
        ret
BEEP    ENDP

; Jumping to this location is like retskp.  It assumes the instruction
;   after the call is a jmp addr.

RSKP    PROC    NEAR
        pop bp
        add bp,3
        push bp
        ret
RSKP    ENDP

; Jumping here is the same as a ret.

R       PROC    NEAR
        ret
R       ENDP

term    proc    near
        mov si,ax               ; this is source
        mov di,offset ourarg    ; place to store arguments
        mov ax,ds
        mov es,ax               ; address destination segment
        mov cx,size termarg
        rep movsb               ; copy into our arg blk
term1:  call prtchr
        jmp short term2         ; have a char...
        nop
        nop
        jmp short term3         ; no char, go on
term2:  and al,7fh
        push ax
        mov dl,al
        mov ah,dconio
        int dos                 ; write out the character
        pop ax
        test ourarg.flgs,capt   ; capturing output?
        jz term3                ; no, forget it
        call ourarg.captr       ; else call the routine
term3:  mov ah,dconio
        mov dl,0ffh
        int dos
        or al,al
        jz term1                ; no character, go on
        cmp al,ourarg.escc      ; escape char?
        je term4                ; yes, exit
        push ax                 ; save char
        mov ah,al
        call outchr             ; output the character
        nop
        nop
        nop
        pop ax
        test ourarg.flgs,lclecho ; echoing?
        jz term1                ; no, continue loop
        mov dl,al
        mov ah,dconio
        int dos
        jmp term1               ; else echo and keep going
term4:  ret
term    endp
code    ends
        end