Piper's Pit BBS/FTP: ibm 0020

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

/ Piper's Pit BBS/FTP: ibm 0020 - 0029 / ibm0020-0029 / ibm0028.tar / ibm0028 / GRLF-C-2.ZIP / GFUNC / PARINT.ASM < prev next >

Wrap

Assembly Source File | 1990-05-30 | 14.5 KB | 616 lines

page 58,132 ;/* ;** parint.asm ;** contains: PrBufC(), stopprt(), strtprt(), testprt() ;*/ include model.h include prologue.h DOSCALL equ 21h ;Dos: call software interrupt number DOSGETVECTOR equ 35h ;Dos: Get Interrupt vector function number DOSSETVECTOR equ 25h ;Dos: Set Interrupt vector ;==>-- PARINT is the structure that holds the state information for ; a parallel port. ; PARINT struc StatusBits dw ? ;Status of channel BaseIOPAR dw ? ;Base I/O Address for LPT IntNum dw ? ;Interrupt Number PrevVector dd ? ;Previous value for interrupt vector PrevBase2 dw ? ;Previous value for interrupt enable port Irq8259 dw ? ;Interrupt # in 8259 Prev8259 dw ? ;Previous 8259 bit IOAdd8259 dw ? ;I/O address of 8259 pBufSize dw ? ;Size of buffer pBufCount dw ? ;Number of characters currently in buffer pBufHead dw ? ;Offset into buffer for head pBufTail dw ? ;Offset into buffer for tail pBuffer dw ptrsize dup(?) ;points to actual buffer PARINT ends PARBUFFERFULL equ -800 ;buffer is full error ifdef LATTICE ;==>-- Define bits in the StatusBits member (Lattice) ; BUFFEREMPTY equ 1000000000000000b ;Buffer is empty BUFFERFULL equ 0100000000000000b ;Buffer is full INTSRUNNING equ 0010000000000000b ;Interrupts are running INTSENABLED equ 0001000000000000b ;Interrupts enabled else ;==>-- Define bits in the StatusBits member (non-Lattice) ; BUFFEREMPTY equ 0000000000000001b ;Buffer is empty BUFFERFULL equ 0000000000000010b ;Buffer is full INTSRUNNING equ 0000000000000100b ;Interrupts are running INTSENABLED equ 0000000000001000b ;Interrupts enabled endif ;==>-- Bits for the parallel control port ; PARSTROBE equ 00000001b ;Parallel strobe bit (active low) PARAUTOFEED equ 00000010b ;Auto feed bit (active low) PARINITPRINTER equ 00000100b ;Initialize printer bit PARSELECTINPUT equ 00001000b ;Select bit (active low) PARIRQENABLE equ 00010000b ;Interrupt enable bit dseg dparint if _LDATA printerstruct dd 0 ;32 bit pointer to PARINT else printerstruct dw 0 ;16 bit pointer to PARINT endif endds pseg cparint ;==>-- The StrobePrinter macro creates the strobe signal for the printer. ; The assumption is made that upon entry the DX register contains the ; address of the parallel control port. ; StrobePrinter macro mov al,PARIRQENABLE+PARSELECTINPUT+PARINITPRINTER+PARSTROBE out dx,al jmp short $+2 ;delay jmp short $+2 ; " jmp short $+2 ; xor al,PARSTROBE out dx,al endm ;/* ;** int ;** PrBufC(PARINT *p,unsigned char character) ;** ;** ARGUMENT(s) ;** p - Points to PARINT structure returned from ;** OpenPrinter(). ;** ;** character - Character to be put in the printer buffer. ;** ;** ;** DESCRIPTION ;** Puts a character in the printer buffer. ;** ;** ;** RETURNS ;** 0 if successful, else: ;** ;** PARBUFFERFULL ;** ;** AUTHOR ;** "" Thu 17-Nov-1988 11:50:48 ;** Copyright (C)1988-1990 Greenleaf Software Inc. All Rights Reserved. ;** ;** MODIFICATIONS ;** ;*/ cproc PrBufC push es if _LDATA push ds lds si,parm1_ ;DS:SI points to PARINT mov al,parm3_ ;AL = character else mov si,parm1_ ;DS:SI points to PARINT mov al,parm2_ ;AL = character endif test [si+StatusBits],BUFFERFULL jz bufnotfull mov ax,PARBUFFERFULL jmp short prbufcex bufnotfull: lea di,[si+pBufSize] cli call insert ;insert character in buffer jnz notful2 ;if buffer did not go full jump or [si+StatusBits],BUFFERFULL ;set bit that says buffer is full notful2: sti xor ax,ax ;assume success test [si+StatusBits],BUFFEREMPTY ;did we put character in empty buffer? jz prbufcex ;if not jump out and [si+StatusBits],not BUFFEREMPTY ;else say buffer not now empty test [si+StatusBits],INTSENABLED jz prbufcex ;if ints not enabled get out test [si+StatusBits],INTSRUNNING jnz prbufcex mov dx,[si+BaseIOPAR] ;see if printer is ready inc dx in al,dx test al,80h ;is printer ready for character jz prbufcex lea di,[si+pBufSize] cli call remove ;remove character from buffer jnz notempt1 ;see if it went empty or [si+StatusBits],BUFFEREMPTY notempt1: or [si+StatusBits],INTSRUNNING sti mov dx,[si+BaseIOPAR] ;DX = base address of Parallel port out dx,al ;output character to port inc dx inc dx jmp short $+2 jmp short $+2 StrobePrinter xor ax,ax ;indicate success prbufcex: if _LDATA pop ds endif pop es cproce ;/* ;** void ;** stopprt(PARINT *p) ;** ;** ARGUMENT(s) ;** p - points to PARINT structure to stop ;** ;** ;** DESCRIPTION ;** Halts printer output, does not remove characters from buffer, ;** does not disable interrupt system. ;** ;** RETURNS ;** void ;** ;** AUTHOR ;** "" Fri 18-Nov-1988 11:11:41 ;** Copyright (C)1988-1990 Greenleaf Software Inc. All Rights Reserved. ;** ;** MODIFICATIONS ;** ;*/ cproc stopprt if _LDATA push ds lds si,parm1_ else mov si,parm1_ endif and [si+StatusBits],not INTSRUNNING+INTSENABLED if _LDATA pop ds endif cproce ;/* ;** void ;** _closepar(PARINT *p) ;** ;** ARGUMENT(s) ;** p - points to PARINT structure to close ;** ;** DESCRIPTION ;** Restores modes set in parallel port and 8259 and interrupt ;** vectors to their pre-opened condition. This function should ;** only be called by the ClosePrinter() function. ;** ;** RETURNS ;** void ;** ;** AUTHOR ;** "" Thu 17-Nov-1988 11:11:06 ;** Copyright (C)1988-1990 Greenleaf Software Inc. All Rights Reserved. ;** ;** MODIFICATIONS ;** ;*/ cproc _closepar,,_closepa push es push ds if _LDATA lds si,parm1_ else mov si,parm1_ endif mov dx,[si+BaseIOPAR] ;CX = base I/O address for port add dx,2 ;DX = IRQ enable port mov al,byte ptr [si+PrevBase2] ;Restore parallel port out dx,al ;to it's pre-open setting mov cx,[si+Irq8259] mov ax,1 shl al,cl mov cx,ax mov dx,[si+IOAdd8259] ;DX=Base I/O Address of 8259 inc dx in al,dx jmp short $+2 or al,cl ;assume previously disabled test [si+Prev8259],cx ;check assumption jnz rs8259 ;if assumption correct xor al,cl ;else reverse assumption rs8259: out dx,al ;restore to previous state push ds ;now restore the interrupt vector mov al,byte ptr [si+IntNum] ;Interrupt Vector # lds dx,[si+PrevVector] ;DS:DX = old value mov ah,DOSSETVECTOR int DOSCALL pop ds pop ds pop es cproce ;/* ;** void ;** strtprt(PARINT *p) ;** ;** ARGUMENT(s) ;** p - points to PARINT structure to start ;** ;** ;** DESCRIPTION ;** Re-starts printer output, assume printer has been halted with ;** StopPrinter(). ;** ;** RETURNS ;** void ;** ;** AUTHOR ;** "" Fri 18-Nov-1988 11:11:41 ;** Copyright (C)1988-1990 Greenleaf Software Inc. All Rights Reserved. ;** ;** MODIFICATIONS ;** ;*/ cproc strtprt if _LDATA push ds lds si,parm1_ else mov si,parm1_ endif or [si+StatusBits],INTSENABLED test [si+StatusBits],INTSRUNNING ;are they running jnz startexit ;if so leave mov dx,[si+BaseIOPAR] ;see if printer is ready inc dx in al,dx test al,80h ;is printer ready for character jz startexit lea di,[si+pBufSize] cli call remove ;remove character from buffer jnz stnotempt1 ;see if it went empty or [si+StatusBits],BUFFEREMPTY stnotempt1: or [si+StatusBits],INTSRUNNING sti mov dx,[si+BaseIOPAR] ;DX = base address of Parallel port out dx,al ;output character to port inc dx stloop1: in al,dx test al,80h jz stloop1 inc dx StrobePrinter startexit: if _LDATA pop ds endif cproce ;/* ;** void ;** _setpari(PARINT *p) ;** ;** ARGUMENT(s) ;** p - points to PARINT structure to setup ;** ;** DESCRIPTION ;** Enables interrupt mode operation for a parallel device as described ;** in a PARINT structure. This function should only be called by the ;** OpenPrinter() function. ;** ;** RETURNS ;** void ;** ;** AUTHOR ;** "" Wed 16-Nov-1988 09:42:30 ;** Copyright (C)1988-1990 Greenleaf Software Inc. All Rights Reserved. ;** ;** MODIFICATIONS ;** ;*/ cproc _setpari push es push ds if _LDATA les si,parm1_ mov word ptr printerstruct,si mov word ptr printerstruct+2,es mov ax,es mov ds,ax ;DS:SI points to structure else mov si,parm1_ mov printerstruct,si ;DS:SI points to structure endif mov ah,DOSGETVECTOR mov al,byte ptr [si+IntNum] ;Get current value of vector int DOSCALL ;to ES:BX mov word ptr [si+PrevVector],bx mov word ptr [si+PrevVector+2],es push ds ;now set the vector of our handler mov ah,DOSSETVECTOR mov al,byte ptr [si+IntNum] mov bx,cs mov ds,bx mov dx,offset IRQ7Routine ;set new vector to DS:DX int DOSCALL pop ds ;Get DS back mov dx,[si+BaseIOPAR] ;CX = base I/O address for port add dx,2 ;DX = IRQ enable port in al,dx ;read current value mov byte ptr [si+PrevBase2],al ;and save in structure mov al,PARIRQENABLE+PARSELECTINPUT+PARINITPRINTER jmp short _fpf _fpf: out dx,al ;enable interrupts on parallel port mov cx,[si+Irq8259] ;get 8259 enable bit mov al,1 shl al,cl ;shift 1 bit into position not al ;ones complement it mov cl,al ;save in cl mov dx,[si+IOAdd8259] ;dx=8259 base inc dx in al,dx jmp short _fpf2 _fpf2: xor ah,ah mov [si+Prev8259],ax and al,cl ;enable correct bit out dx,al ;in 8259 pop ds pop es cproce ;/* ;** unsigned char ;** testprt(PARINT *p) ;** ;** ARGUMENT(s) ;** p - points to PARINT structure ;** ;** DESCRIPTION ;** Gets the hardware status of the printer. ;** ;** ;** RETURNS ;** ;** Bit Meaning ;** 7 Busy ;** 6 Ack ;** 5 Out of paper ;** 4 Select ;** 3 Error ;** ;** AUTHOR ;** "" Fri 18-Nov-1988 12:07:30 ;** Copyright (C)1988-1990 Greenleaf Software Inc. All Rights Reserved. ;** ;** MODIFICATIONS ;** ;*/ cproc testprt if _LDATA push ds lds si,parm1_ else mov si,parm1_ endif mov dx,[si+BaseIOPAR] ;get port # to DX inc dx in al,dx and al,0f8h ;mask unused bits xor ah,ah if _LDATA pop ds endif cproce ;/* ;** DESCRIPTION ;** Interrupt routine for IRQ #7 (printer). Saves all registers and ;** points DS:SI to the PARINT data structure which contains state ;** information for the parallel port using IRQ 7. ;** ;** AUTHOR ;** "" Wed 16-Nov-1988 09:55:13 ;** Copyright (C)1988-1990 Greenleaf Software Inc. All Rights Reserved. ;** ;** MODIFICATIONS ;** ;*/ IRQ7Routine proc far sti push ax push dx push es push ds push bx push cx push si push di ifdef TURBOC if _HUGE mov ax,_dparint_DATA else mov ax,DGROUP endif else ifndef AZTEC mov ax,DGROUP else mov ax,dataseg endif endif mov ds,ax if _LDATA lds si,printerstruct else mov si,printerstruct endif cld call ProcessIRQ mov dx,[si+IOAdd8259] ;Load registers for 8259 EOI mov al,20h pop di pop si pop cx pop bx pop ds pop es cli out dx,al ;re-enable 8259 pop dx pop ax iret IRQ7Routine endp ;==>-- Arrive here with DS:SI pointing to a PARINT data structure ; ProcessIRQ proc near mov dx,[si+BaseIOPAR] ;read status port to clear inc dx ;interrupt condition in al,dx test [si+StatusBits],INTSENABLED jz stopirq test [si+StatusBits],BUFFEREMPTY jz IRQbufnotempty ;if buffer not empty continue stopirq: and [si+StatusBits],not INTSRUNNING jmp short IRQExit IRQbufnotempty: lea di,[si+pBufSize] call remove ;remove character from buffer jnz didnotgoempty ;if buffer did not go empty take jump or [si+StatusBits],BUFFEREMPTY didnotgoempty: and [si+StatusBits],not BUFFERFULL ;cannot be full now mov dx,[si+BaseIOPAR] ;get base of parallel port out dx,al ;send character to printer jmp short $+2 jmp short $+2 inc dx inc dx StrobePrinter IRQExit: ret ProcessIRQ endp ;==>-- Offsets for the insert & remove routines ; BSIZE equ 0 COUNT equ 2 HEAD equ 4 TAIL equ 6 BUFFER equ 8 ;==>-- insert character is to be called with ds:di pointing to the ; size variable, upon return the Zero flag being set indicates ; that the buffer is NOW FULL. When the buffer is full do not call ; this routine again, until there is space for another character. ; Call with character in AL. This routine does not test for a ; full buffer before inserting, only after inserting. ; insert proc near ;DS:DX points to beginning push si if _LDATA push es les si,[di+BUFFER] ;es:si points to base of array else mov si,[di+BUFFER] ;ds:si points to base of array endif inc word ptr [di+COUNT] ;bump counter mov bx,[di+TAIL] ;read the tail mov dx,bx inc dx ;advance the tail for next mov cx,[di+BSIZE] ;get size of buffer to cx cmp dx,cx ;check for wrap jb inwrap ;if no wrap take jump xor dx,dx ;reset subscript to 0 inwrap: mov [di+TAIL],dx ;save updated tail if _LDATA mov es:[si+bx],al ;save character via ES:SI else mov [si+bx],al ;save character via DS:SI endif jmp short inend inend: cmp dx,[di+HEAD] ;see if buffer full if _LDATA pop es endif pop si ret insert endp ;==>-- remove character is to be called with ds:di pointing to the ; size variable, upon return the Zero flag being set indicates ; that the buffer is NOW EMPTY. When the buffer is empty DO NOT call ; this routine again, until there is another character to remove. ; Returns with character in AL. This routine does not test for an ; empty buffer before removing, only after removing. ; remove proc near push si if _LDATA push es les si,[di+BUFFER] ;es:si=base of buffer else mov si,[di+BUFFER] ;ds:si=base of buffer endif dec word ptr [di+COUNT] ;decrement counter mov bx,[di+HEAD] ;read the head mov dx,bx inc dx mov cx,[di+BSIZE] ;get size of buffer to cx cmp dx,cx ;check for wrap jb rewrap ;if no wrap take jump xor dx,dx ;reset subscript to 0 rewrap: mov [di+HEAD],dx ;save updated head xor ah,ah if _LDATA mov al,es:[si+bx] ;remove character via ES:SI else mov al,[si+bx] ;remove character via DS:SI endif jmp short reend reend: cmp dx,[di+TAIL] ;see if buffer empty if _LDATA pop es endif pop si ret remove endp endps end