Shareware Grab Bag

home *** CD-ROM | disk | FTP | other *** search

/ Shareware Grab Bag / Shareware Grab Bag.iso / 001 / acomclip.arc / COMM_IO.ASM next >

Wrap

Assembly Source File | 1986-12-09 | 22.0 KB | 612 lines

page,132 ;------------------------------------------------------------------------------- ; ---- COMM_IO.ASM ---- ; To use it just MODE your COM1: to whatever speed you like, I've only tested ; it to 9600 baud it does'nt use DOS calls so its pretty fast I dont know ; how it will effect non IBM hardware, works just fine on PC'S Limited 286-8. ; It may not be fully debugged, I have'nt tested the XON or XOFF functions ; Simple communications work fine, It ignores the modem control line so to use ; it you must provide software handshaking for a terminal that does'nt have a ; buffer. ; The recieving buffer is 512 bytes so as long as you dont let it fillup you ; wont loose any characters, of coarse you could make it as larger if necessary. ; ; ; Filename: COMM_IO ; Program.: Clipper Communication for Com1: ; Authors.: Curt Klinsing,Modifed by Patrick Jonte ; Date....: April 20, 1986 ; ; Function: A set of Clipper W85 callable functions to support ; interrupt driven character I/O on the IBM PC. Input ; is buffered, output is polled. ; ; ; ; 1- OUTP_CHAR {call} outputs a character string up to first null encountered. ; (Note- all clipper strings are terminated by a ascii null or hex 00) ; Example: ; PUTCHARS='a character string ' ; CALL OUTP_CHAR WITH PUTCHARS ; ; 2- INP_CHAR(.T.or.F.) {function} returns a character string of the characters ; available in the input buffer (maximum of 512 characters) ; and gives the option of deleting characters read from input buffer .T. or ; .F. leaving it untouched which allows easy monitoring for a special ; character(s) ; Example: ; RECV_STR=INP_CHAR(.T.) & reads buffer and kills characters read ; from buffer ; ; 3- INP_CNT() {function} returns numeric indicating the number of characters ; that the input buffer is holding (Maximum of 512). ; Example: ; NUMCHAR=INP_CNT() ; ; 4- SET_XOFF {CALL} enables or disables xoff control . ; Example: ; SOFF=.T. && if you want to turn xoff feature on ; SOFF=.F. && to turn it off ; CALL SET_XOFF WITH SOFF ; ; 5- GET_XOFF(),RECV_XOFF(),SENT_XOFF() {FUNCTION} return logical value ; indicating state of control flags ; Example: ; GFLAG=GET_XOFF() ; ; 6- INIT_COMM,UNINIT_COM,INP_FLUSH {CALL} dont pass or return parameters ; Example: ; CALL INIT_COMM ; CALL INP_FLUSH ;--------------------------------------------------------------------------- ; name COMM_IO public init_comm ;initialize the comm port, public uninit_com ;remove initialization, public set_xoff ;enable/disable XON/XOFF, public get_xoff ;read XON/XOFF state, public rcvd_xoff ;returns true if XOFF rcvd, public sent_xoff ;true if XOFF sent, public inp_cnt ;returns count of rcv chars, public inp_char ;get char string from buffer, public inp_flush ;flush input buffer, public outp_char ;output a character string, ; extrn _retc:far ; return character string extrn _retds:far ; return date type from date string "YYYYMMDD" extrn _retl:far ; return logical true or false extrn _retni:far ; return word as numeric extrn _retnl:far ; return double word as numeric extrn _retnd:far ; return floating point as numeric ; extrn _parc:far ; pass character string extrn _parni:far ; pass integer numeric extrn _parnl:far ; pass integer long numeric extrn _parnd:far ; pass double numeric extrn _parl:far ; pass logical integer extrn _pards:far ; pass date string "yyyymmdd" ; extrn _parinfo:far ; UNDEF 0 ; CHARACTER 1 ; NUMERIC 2 ; LOGICAL 4 ; DATE 8 ; ALIAS 16 ; MPTR 32 ; MEMO 65 ; WORD 128 _prog segment byte public 'code' assume cs:_prog ; ; FALSE EQU 0 TRUE EQU NOT FALSE BASE EQU 03F8H ;BASE FOR SERIAL BOARD COMM1 LCR EQU BASE+3 ; Line control register IER EQU BASE+1 ; Interrup Enable Register MCR EQU BASE+4 ; modem control register EnblDRdy EQU 01H ; enable 'data-ready' interrupt bit IntCtlr EQU 21H ; OCW 1 FOR 8259 CONTROLLER EnblIRQ4 EQU 0EFH ; Enable COMMUNICATIONS (IRQ4) COMM1 DATAPORT EQU BASE ; transmit/receive data port MaskIRQ4 EQU 10H ; BIT TO DISABLE COMM INTERRUPT (IRQ4) MDMSTA EQU BASE+5 ; line status register MDMMSR EQU BASE+6 ; modem status register MDMBAD EQU BASE ; lsb baud resgister MDMBD1 EQU BASE+1 ; msb baud rate register MDMCD EQU 80H ; mask for carrier dectect SETBAU EQU 80H ; code for Divisor Latch Access Bit MDMTBE EQU 20H ; 8250 tbe flag MDMBRK EQU 40H ; command code for 8250 break LINMOD EQU 03H ; line mode=8 bit, no parity MDMMOD EQU 0BH ; modem mode = DTR and RTS HIGH STOP2 EQU 04H ; BIT FOR TWO STOP BITS IF BAUD<300 RS8259 EQU 20H ; OCW 3 FOR 8259 RSTINT EQU 64H ; SPECIFIC EOI FOR COMM INTERRUPT XOFF EQU 13H ; XOFF character XON EQU 11H ; XON character ; ; MISCELLANEOUS EQUATES ; CR EQU 13 LF EQU 10 DosCall EQU 33 ;INTERRUPT NUMBER FOR DOS CALL CNSTAT EQU 11 ;FUNCTION NUMBER FOR CONSOLE STATUS CNIN EQU 1 ;FUNCTION NUMBER FOR CONSOLE INPUT BUFSIZ EQU 512 ;Max NUMBER OF CHARS SetIntVect EQU 25H ;SET INTERRUPT VECTOR FUNCTION NUMBER ; ; DUMP BUFFER, COUNT AND POINTER. ; CIRC_BUF DB BUFSIZ DUP(?) ;ALLOW 512 MAXIMUM BUFFERED CHARACTERS BUF_TOP EQU $ - 1 ;KEEP TRACK OF THE TOP OF THE BUFFER OUT_BUF DB BUFSIZ DUP(?) ;TEMP BUFF AREA FOR CALLING PROCEDURE CIRC_TOP DW BUF_TOP ; CIRC_IN DW OFFSET CIRC_BUF ;POINTER TO LAST CHAR. PLACED IN BUFFER CIRC_CUR DW OFFSET CIRC_BUF ;POINTER TO NEXT CHAR. TO BE RETRIEVED FROM ; BUFFER CIRC_CT DW 0 ;COUNT OF CHARACTERS USED IN BUFFER SNT_XOFF DB FALSE ;FLAG TO CHECK IF AN XOFF HAS BEEN SEND GOT_XOFF DB FALSE ;FLAG TO CHECK IF AN XOFF HAS BEEN RECEIVED SEE_XOFF DB FALSE ;FLAG TO SEE IF WE ARE INTERESTED IN XON/XOFF CIRC_OUT DW 0 ;NUMBER OF CHARACTERS RETURNED TO CLIPPER INTR_CUR DW 0 ;BUFFER FOR INP_CHAR INTR_CT DW 0 ;BUFFER FOR INP_CHAR KILLSTR DB 0 ;FLAG PASSED TO KILL BUFFER UPON READING ; ; ; ;set_xoff(flag) Enable (flag = 1 ) or disable ;int flag; (flag = 0 ) XON/ XOFF protocol ; for the character input stream. ;If enabled, an XOFF will be sent when the buffer ;reaches 3/4 full. NOTE: an XON will not be sent auto- ;matically. Your program must do it when it sees ;the rcvd_xoff() flag, and ready for more chars. ; set_xoff proc far push bp mov bp,sp PUSH DS ;SAVE DATA SEGMENT lds si,dword ptr [bp+6] ; get calling varible addr off stack xor ax,ax lodsb ; load al with calling variable push cs pop ds ; move code seg addr to data seg reg. cmp al,0 ; check for logic 0 jnz to_on ; if not 0 set it true=-1 mov see_xoff,FALSE jmp done1 to_on: mov see_xoff,TRUE done1: pop ds pop bp ret set_xoff endp ; ;flag= get_xoff() Returns the current setting ; of the XON/ XOFF flag set ;by set_xoff(), above. ; get_xoff proc far push ds push cs pop ds ; move code seg addr to data seg reg. xor ax,ax ; zero out ax mov al,see_xoff ; get the flag -1=true 0=false neg al ; make it a positive pop ds push ax call _retl ; return it to clipper a logical value pop ax ; adjust the stack ret get_xoff endp ; ;flag= sent_xoff(); Returns true if an XOFF ; character was sent, indicating ; the receive buffer is 3/4 full. ; sent_xoff proc far push ds ; save data seg reg push cs pop ds ; move code seg addr to data seg reg. xor ax,ax ; zero out ax mov al,snt_xoff neg al ; make it positive pop ds push ax call _retl ; return it to clipper pop ax ret sent_xoff endp ; ;rcvd_xoff() Returns true if an XOFF was ; received; will return false as ;soon as an XON is received. Does not effect data output, ;only indicates the above. (Obviously useless for binary ;data.) ; rcvd_xoff proc far push ds ; save data seg reg push cs pop ds ; move code seg addr to data seg reg. xor ax,ax ; zero out ax mov al,got_xoff neg al pop ds push ax call _retl pop ax ret rcvd_xoff endp ; ;count= inp_cnt() Returns the number of characters ; available in the input buffer. ; inp_cnt proc far push ds ; save data seg reg push cs ; pop ds ; move code seg addr to data seg reg mov bx,circ_ct pop ds push bx call _retni ; return to clipper a integer value pop bx ret inp_cnt endp ; ;inp_flush() Flush the input buffer. ; inp_flush proc far push ds ; save data reg push cs pop ds ; move code seg addr to data seg reg. mov bx,offset circ_buf mov circ_in,bx mov circ_cur,bx ; point the buffer pointer to the begining xor ax,ax mov circ_ct,ax ; set the buffer cntr to zero xor cx,cx mov cl,see_xoff ;check if interested in xon/xoff cmp cl,TRUE jnz clnup3 ;not interested, so goto return cmp snt_xoff,TRUE ;have we sent an xoff? jnz clnup3 ;no, so return mov snt_xoff,FALSE mov cl,XON push ax ; save char call comout ; transmit xon char pop ax clnup3: pop ds ret inp_flush endp ; --------- Init ----------------------------------- ; Program initialization: ; -- Set up vector for RS232 interrupt (0CH) ; -- Enbl IRQ4 ; -- Enbl RS232 interrupt on data ready ; ; --------------------------------------------------- init_comm proc far push bp cli ; ; ---- Set up INT x'0C' for IRQ4 ; push ds push cs pop ds ;cs to ds mov dx,offset IntHdlr ;relative adddres of interrupt handler mov al,0cH ;interrupt number for comm. mov ah,SetIntVect ;function number for setting int vector int DosCall ;set interrupt in 8086 table pop ds ;restore DS ; ; ---- Enbl IRQ4 on 8259 interrupt controller ; cli in al,IntCtlr ; get current masks and al,EnblIRQ4 ; Reset IRQ4 mask out IntCtlr,al ; And restore to IMR ; ; --- Enbl 8250 data ready interrupt ; mov dx,LCR ; DX ==> LCR in al,dx ; Reset DLAB for IER access and al,7FH out dx,al mov dx,IER ; Interrupt Enbl Register mov al,EnblDRdy ; Enable 'data-ready' interrupt out dx,al ; ; --- Enbl OUT2 on 8250 ; mov dx,MCR ; modem control register mov al,0AH ; Enable OUT2 & RTS,DTR out dx,al sti pop bp ret init_comm endp ; ;uninit_com() Removes the interrupt structure ; installed by init_com(). Must be ;done before passing control to the DOS, else chars received ;will be stored into the next program loaded! ; uninit_com proc far push bp ; --- Disable IRQ4 on 8259 ; cli in al,IntCtlr ;GET OCW1 FROM 8259 or al,MaskIRQ4 ;DISABLE COMMUNICATIONS INTERRUPT out IntCtlr,al ; ; --- Disable 8250 data ready interrupt ; mov dx,LCR ; DX ==> LCR in al,dx ; Reset DLAB for IER access and al,7FH out dx,al mov dx,IER ; Interrupt Enbl Register mov al,0 ; Disable all 8250 interrupts out dx,al ; ; --- Disable OUT2 on 8250 ; mov dx,MCR ; modem control register mov al,0 ; Disable OUT2 out dx,al sti pop bp ret uninit_com endp ; ;char inp_char() Returns a character string from the input ; buffer. [see header note for details] ; ; inp_char proc far push es ; save extra reg push ds ; save data reg cld ; mov ax,0 push ax call _parinfo ; make sure there is 1 parameter pop bx cmp ax,1 jnz I30 ; mov ax,1 push ax call _parinfo ; make sure parameter is logical type pop bx cmp ax,4 jnz nodeflt ; mov ax,1 ; get parameter push ax ; put it on the stack call _parl ; get the parameter from clipper pop es ; dummy pop to fixup stack jmp nodeflt I30: mov al,1 nodeflt: push cs pop ds ; move code seg addr to data seg reg. push ds pop es ; load the target segment reg mov di,offset out_buf ; " " " offset reg push circ_ct pop intr_ct push circ_cur pop intr_cur mov killstr,al xor ax,ax mov circ_out,ax ; zero the output count do_agan: cmp intr_ct,0 ; exit if the buffer is empty jz no_more cmp circ_out,length circ_buf ; dont pass more than buffer size jz no_more mov bx,intr_cur xor ax,ax mov al,[bx] ;get next char from circ_buf cmp killstr,1 jnz ktrak dec circ_ct ;decrement circ_buf COUNT ktrak: dec intr_ct cmp bx,circ_top ;ARE WE AT THE TOP OF THE circ_buf? jz reset_cur ;JUMP IF SO inc bx ;ELSE, BUMP PTR jmp short upd_cur reset_cur: mov bx,OFFSET circ_buf ;RESET circ_in TO BOTTOM OF BUF. upd_cur: mov intr_cur,bx ;SAVE NEW PTR cmp killstr,1 jz clnup2 xor cx,cx mov cl,see_xoff ;check if interested in xon/xoff cmp cl,TRUE jnz clnup2 ;not interested, so goto return cmp snt_xoff,TRUE ;have we sent an xoff? jnz clnup2 ;no, so return cmp circ_ct,80h ;yes, so see in buf is now emptying jg clnup2 ;not empty enuf to send xon, jump to ret mov snt_xoff,FALSE mov cl,XON push ax ; save char call comout ; transmit xon char pop ax clnup2: inc circ_out ;inc the output counter stosb ;move the recv char to the output buffer jmp do_agan ;go see if we can get another character no_more: xor ax,ax stosb ;add a null to terminate the recv string ; cmp killstr,1 jnz nokill push intr_cur pop circ_cur nokill: mov bx,offset out_buf mov ax,seg out_buf pop ds pop es push ax push bx call _retc ; push the segment and offset and return the pop bx ; character string to clipper pop ax ret ; ; inp_char endp ;outp_char(c) Output the character string to the ; serial port. This is not buffered ; or interrupt driven. It will output ; the ascii string until a null in ; encountered. ; outp_char proc far push bp mov bp,sp push ds lds si,dword ptr [bp+6] ; get the addr of varible string cld ; make lodsb inc the var pointer D20: lodsb cmp al,00 ; is it the last char in string jz D30 mov cl,al ; get the transmit char to cl push ds push cs ; load code seg with data seg pop ds ; push ax ; push dx ; xor ax,ax ; xor dx,dx ; mov dl,cl ; this code will echo the ; mov ah,2 ; characters to the screen ; int DosCall ; pop dx ; pop ax sti ; set the interupt flag call comout ; transmit a char pop ds jmp D20 ; get the next char D30: pop ds pop bp ret outp_char endp ; ;Local subroutine: output CL to the port. ; comout: mov dx,MDMSTA in al,dx ; get 8250 status and al,MDMTBE ; check for transmitter ready jz comout ; jump if not to wait mov al,cl ; get char to al mov dx,DATAPORT out dx,al ; output char to 8251 ret ; ; RECEIVE INTERRUPT HANDLER (CHANGED TO PLACE CHARACTERS IN A ; CIRCULAR circ_buf AND TO SEND AN XOFF IF THE circ_buf IS MORE THAN ; 3/4 FULL - S.G.) ; IntHdlr: cli push cx push dx push bx push ax push ds mov ax,cs ;get cur code segment mov ds,ax ; and set it as data segment mov bx,circ_in ;GET circ_buf IN PTR mov dx,dataport ;GET DATA PORT NUMBER in al,dx ;GET RECEIVED CHARACTER ; push ax ; push dx ; xor ax,ax ; xor dx,dx ; mov dl,al ; this code will echo the ; mov ah,2 ; characters to the screen ; int DosCall ; pop dx ; pop ax xor cx,cx mov cl,see_xoff ;check if interested in xon/xoff cmp cl,TRUE jnz ck_full ;not interested goto ck if buf full mov cl,al ;put char in cl for testing and cl,7fh ;turn off any parity bits cmp cl,XOFF ;see if we got an xoff jnz ck_xon mov got_Xoff,TRUE ; code for handling xon/xoff from remote jmp clnup ck_xon: cmp cl,XON jnz reg_ch mov got_Xoff,FALSE jmp clnup ; ;Normal character; not XON/XOFF, or XON/XOFF disabled. ; reg_ch: test snt_Xoff,TRUE ;SEE IF sentXoff IS SET jnz ck_full ;IF SO, DON'T SEND ANOTHER XOFF cmp circ_ct,(BUFSIZ * 3)/4 ;ALLOW BUF TO BECOME 3/4 FULL BEFORE ; SENDING XOFF jb savch ;IF IT'S OK, CONTINUE push ax ;SAVE CHARACTER mov CL,XOFF ;GET XOFF CHARACTER mov snt_Xoff,TRUE ;RESET sentXoff call comout ; AND SEND IT pop ax ;RETRIEVE CHARACTER jmp short savch ;IF WE'RE HERE, THE circ_buf HAS BUFSIZ-80H ; CHARACTERS ck_full: cmp circ_ct,BUFSIZ ;SEE IF circ_buf ALREADY FULL jz clnup ; JUMP IF SO, DO NOT PLACE CHARACTER IN BFR savch: mov [bx],AL ;SAVE NEW CHARACTER IN circ_buf inc circ_ct ;BUMP circ_buf COUNT cmp bx,circ_top ;ARE WE AT THE TOP OF THE circ_buf? jz reset_in ;JUMP IF SO inc bx ;ELSE, BUMP PTR jmp short into_buf reset_in: mov bx,OFFSET circ_buf ;RESET circ_in TO BOTTOM OF BUF. into_buf: mov circ_in,bx ;SAVE NEW PTR clnup: mov AL,RSTINT out RS8259,AL ;ISSUE SPECIFIC EOI FOR 8259 pop ds ;GET BACK ENTERING DS pop ax pop bx pop dx pop cx sti iret ; _prog ends end