Chip 1997 March

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Assembly Source File | 1989-06-24 | 18.7 KB | 840 lines

page 58,132 .286c .MODEL LARGE ;********************************************************************** ;* * ;* Equates * ;* * ;********************************************************************** tccount equ 72 ;reload count to produce 16572 Hz countmax_18hz equ 910 ;ratio of new timer rate to old rate tcaddrc equ 43h ;timer/counter control register address tcaddrd equ 40h ;timer/counter data register zero tcmode equ 34h ;mode control byte for timer/counter ppiaddr equ 61h ;programmable peripheral interface address ;********************************************************************** ;* * ;* Macros * ;* * ;********************************************************************** ljz macro dest local skip jnz skip jmp dest skip: endm ljb macro dest local skip jnb skip jmp dest skip: endm ljbe macro dest local skip jnbe skip jmp dest skip: endm ;********************************************************************** ;* * ;* Global variables * ;* * ;********************************************************************** .DATA even ;don't put these on an odd boundary blockaddr dd 0 ;beginning of memory block blocksize dd 0 ;size of memory block blockend dd 0 ;last address of memory block + 1 currentaddr dd 0 ;pointer to current play position in memory endaddr dd 0 ;address of last byte to be played + 1 datalength dd 0 ;total number of data bytes datacount dd 0 ;number of data bytes already played filladdr dd 0 ;address of next byte to be filled from disk fillcount dd 0 ;number of bytes already read from disk goflag dw 0 ;indicates whether playback is in progress fdoneflag dw 0 ;indicates whether unread data remains in file fileflag dw 0 ;indicates whether data is read from a file filehandle dw 0 ;handle of file containing voice data hookedflag dw 0 ;indicates whether the interrupt is hooked countfor_18hz dw 0 ;counter to determine when to call BIOS shiftcount db 0 ;current bit position within byte ;********************************************************************** ;* * ;* Code * ;* * ;********************************************************************** .CODE bios_timer_routine dd 0 ;we keep this in the code segment ; for access through the CS register ; since the other segment registers ; will contain unknown values when ; this is needed assume ds:DGROUP ;********************************************************************** ;* Speed up the timer tick and set "goflag" * ;********************************************************************** startvoice proc near pushf cli mov al,tcmode out tcaddrc,al mov ax,tccount out tcaddrd,al mov al,ah out tcaddrd,al mov shiftcount,0 mov countfor_18hz,countmax_18hz mov goflag,1 popf ret startvoice endp ;********************************************************************** ;* Slow the timer tick to normal and clear "goflag" * ;********************************************************************** stopvoice proc near pushf cli mov al,tcmode out tcaddrc,al mov al,0 out tcaddrd,al out tcaddrd,al mov goflag,0 mov fdoneflag,0 popf ret stopvoice endp ;********************************************************************** ;* Interrupt service routine * ;********************************************************************** timer_tick proc far push ds push bx push es push ax push cx mov ax,DGROUP mov ds,ax cmp goflag,0 je chain_exit les bx,currentaddr mov ah,es:[bx] mov cl,shiftcount rol ah,cl rol ah,2 and ah,02h in al,ppiaddr and al,0FCh or al,ah out ppiaddr,al inc cl and cl,07h mov shiftcount,cl jnz exit_decide mov ax,es inc bx jnz check_wrap add ax,1000h check_wrap: cmp bx,word ptr blockend jne check_end cmp ax,word ptr blockend+2 jne check_end mov bx,word ptr blockaddr mov ax,word ptr blockaddr+2 check_end: cmp bx,word ptr endaddr jne save_cur_addr cmp ax,word ptr endaddr+2 jne save_cur_addr call stopvoice jmp short exit_decide save_cur_addr: mov word ptr currentaddr,bx mov word ptr currentaddr+2,ax add word ptr datacount,1 adc word ptr datacount+2,0 exit_decide: dec countfor_18hz jnz nochain_exit mov countfor_18hz,countmax_18hz chain_exit: pop cx pop ax pop es pop bx pop ds jmp cs:bios_timer_routine nochain_exit: mov al,20h out 20h,al pop cx pop ax pop es pop bx pop ds iret timer_tick endp ;********************************************************************** ;* Initialization procedure * ;********************************************************************** ;This routine should be called exactly one time before any of the other ; routines in this package are called. It takes no parameters, but returns ; a value indicating success or failure as follows: ;Return value Meaning ;------------ ------- ; 0 success ; 1 voice package already initialized ; 2 wrong CPU, won't run on 8088 or 8086 public PVOICE_INIT PVOICE_INIT proc far push sp pop ax cmp ax,sp je vi_test mov ax,2 ret vi_test: cmp hookedflag,0 je vi_hook mov ax,1 ret vi_hook: enter 0,0 push si push di push ds lea dx,PVOICE_CBREAK mov ax,seg PVOICE_CBREAK mov ds,ax mov ax,2523h int 21h pop ds push ds mov ax,3508h int 21h mov word ptr cs:bios_timer_routine,bx mov word ptr cs:bios_timer_routine+2,es lea dx,timer_tick mov ax,seg timer_tick mov ds,ax mov ax,2508h int 21h pop ds pop di pop si mov hookedflag,1 sub ax,ax leave ret PVOICE_INIT endp ;********************************************************************** ;* Cleanup procedure * ;********************************************************************** ;This will restore the interrupt 8 vector to its original state. This ; routine MUST be called before the main program exits to DOS, unless: ; (a) the program has never called PVOICE_INIT, or (b) the program is ; becoming memory-resident. ;There are no parameters. The return values are 0 for success or 1 if ; the interrupt vector was not in fact hooked. public PVOICE_CLEANUP PVOICE_CLEANUP proc far cmp hookedflag,1 je vc_unhook mov ax,1 ret vc_unhook: enter 0,0 push si push di call stopvoice push ds lds dx,cs:bios_timer_routine mov ax,2508h int 21h pop ds pop di pop si mov hookedflag,0 sub ax,ax leave ret PVOICE_CLEANUP endp ;********************************************************************** ;* Vector restore for Control-Break * ;********************************************************************** public PVOICE_CBREAK PVOICE_CBREAK proc far pusha push ds push es mov ax,DGROUP mov ds,ax call stopvoice call PVOICE_CLEANUP pop es pop ds popa stc ret PVOICE_CBREAK endp ;********************************************************************** ;* "File read catch-up" procedure * ;********************************************************************** ;This must be called frequently from the main program if file reading is ; being used and the length of the data to be played is longer than the ; length of the memory block. The routine checks the progress of the ; address pointer in use by the interrupt service routine and fills in ; more data from the file if necessary. When all the data has been read, ; then "endaddr" is set accordingly. ;There are no parameters. The return values are 0 for success or 1 if ; an error occurred while reading the file. vcat_temp1l equ [bp-4] ;current address from ISR vcat_temp1h equ [bp-2] ;the four stopping points: vcat_temp2l equ [bp-8] ;data length - fill count vcat_temp2h equ [bp-6] vcat_temp3l equ [bp-12] ;current address - fill address vcat_temp3h equ [bp-10] vcat_temp4l equ [bp-16] ;block end - fill address vcat_temp4h equ [bp-14] vcat_temp5l equ [bp-20] ;(boundary) - fill address vcat_temp5h equ [bp-18] vcat_templength equ 20 public PVOICE_CATCHUP PVOICE_CATCHUP proc far enter vcat_templength,0 ;should we even be doing this? cmp fileflag,0 ljz vcat_exit0 cmp fdoneflag,0 ljz vcat_exit0 ;grab a stable value from currentaddr ; since it is changing all the time cli mov ax,word ptr currentaddr mov vcat_temp1l,ax mov ax,word ptr currentaddr+2 mov vcat_temp1h,ax sti ;calculate the forward distance to each of the ; four possible stopping points vcat_getlengths: mov ax,word ptr datalength sub ax,word ptr fillcount mov vcat_temp2l,ax mov ax,word ptr datalength+2 sbb ax,word ptr fillcount+2 mov vcat_temp2h,ax or ax,vcat_temp2l jnz vcat_getgap ;if datalength = fillcount then all ; data has been read cli mov ax,word ptr filladdr mov word ptr endaddr,ax mov ax,word ptr filladdr+2 mov word ptr endaddr+2,ax sti mov fdoneflag,0 jmp vcat_exit0 vcat_getgap: mov ax,vcat_temp1l sub ax,word ptr filladdr mov vcat_temp3l,ax pushf mov ax,vcat_temp1h sub ax,word ptr filladdr+2 sar ax,12 popf sbb ax,0 mov vcat_temp3h,ax or ax,vcat_temp3l jnz vcat_getclearance mov vcat_temp3l,0FFFFh mov vcat_temp3h,0FFFFh vcat_getclearance: mov ax,word ptr blockend sub ax,word ptr filladdr mov vcat_temp4l,ax pushf mov ax,word ptr blockend+2 sub ax,word ptr filladdr+2 sar ax,12 popf sbb ax,0 mov vcat_temp4h,ax mov ax,word ptr filladdr neg ax mov vcat_temp5l,ax mov word ptr vcat_temp5h,0 jnz vcat_cmp1 inc word ptr vcat_temp5h ;select the stopping point which will be ; encountered soonest ;Since we are not interested in the negative ; values, doing unsigned compares in a search ; for the smallest number will give the ; desired result. vcat_cmp1: mov ax,vcat_temp2h mov cx,vcat_temp2l cmp ax,vcat_temp3h jb vcat_cmp3 ja vcat_cmp2 cmp cx,vcat_temp3l jb vcat_cmp3 vcat_cmp2: mov ax,vcat_temp3h mov cx,vcat_temp3l vcat_cmp3: cmp ax,vcat_temp4h jb vcat_cmp5 ja vcat_cmp4 cmp cx,vcat_temp4l jb vcat_cmp5 vcat_cmp4: mov ax,vcat_temp4h mov cx,vcat_temp4l vcat_cmp5: cmp ax,vcat_temp5h jb vcat_cmp7 ja vcat_cmp6 cmp cx,vcat_temp5l jb vcat_cmp7 vcat_cmp6: mov ax,vcat_temp5h mov cx,vcat_temp5l vcat_cmp7: ;Now the smallest number is in AX:CX. ; However, AX:CX may be 65536 or 0FFFFh ; (illegal), so we must test for these ; possibilities. cmp ax,1 je vcat_fixcx cmp cx,0FFFFh jne vcat_readfile vcat_fixcx: mov cx,0FE00h sub ax,ax vcat_readfile: mov bx,filehandle push ds lds dx,filladdr mov ah,3Fh int 21h pop ds jc vcat_error1 cmp ax,cx jne vcat_error1 ;update global varibles to show the current ; situation add word ptr fillcount,cx adc word ptr fillcount+2,0 add word ptr filladdr,cx jnc vcat_fillwrap add word ptr filladdr+2,1000h vcat_fillwrap: mov bx,word ptr blockend cmp bx,word ptr filladdr jne vcat_exit0 mov ax,word ptr blockend+2 cmp ax,word ptr filladdr+2 jne vcat_exit0 mov bx,word ptr blockaddr mov ax,word ptr blockaddr+2 mov word ptr filladdr,bx mov word ptr filladdr+2,ax jmp short vcat_exit0 ;error exit point vcat_error1: mov ax,1 jmp short vcat_exit ;normal exit point vcat_exit0: ;don't leave until at least one bit has been played ; or goflag becomes zero mov ax,word ptr currentaddr cmp vcat_temp1l,ax jne vcat_exitloop cmp goflag,0 jne vcat_exit0 vcat_exitloop: sub ax,ax vcat_exit: leave ret PVOICE_CATCHUP endp ;********************************************************************** ;* "Start playback" procedure * ;********************************************************************** ;Accepts the following parameters with PASCAL parameter-passing convention: ;Position Size Description ;-------- ---- ----------- ; 1 4 A far pointer to the memory block used for voice data. ; 2 4 A dword indicating the length of the memory block. ; 3 2 A flag word. If this is 1, then data will be read from ; a file. If it is 0, then the data is assumed to be ; already present in the memory block. ; 4 2 An open file handle. This is ignored if the flag word ; is 0. ; 5 4 A dword indicating the number of bytes of voice data ; to be played. If the flag word is 0, then this number ; must not be greater than the length of the memory ; block. ; 6 4 A dowrd indicating the offset within the memory block ; where playback is to begin. This number must be less ; than the block length. ;Return value Meaning ;------------ ------- ; 0 success ; 1 data length greater than block size but no file read ; 2 block size is too small (datalength > blocksize and ; blocksize < 8192 and file read = yes) ; 3 unable to read from file ; 4 voice playback is already in progress ; 5 starting offset is not less than block length min_blocksize equ 8192 vs_parm1 equ [bp+22] ;length = 4 vs_parm2 equ [bp+18] ;length = 4 vs_parm3 equ [bp+16] ;length = 2 vs_parm4 equ [bp+14] ;length = 2 vs_parm5 equ [bp+10] ;length = 4 vs_parm6 equ [bp+6] ;length = 4 vs_parmlength equ 20 public PVOICE_START PVOICE_START proc far cmp goflag,0 je vs_begin mov ax,4 ret vs_parmlength vs_begin: enter 0,0 mov word ptr datacount,0 mov word ptr datacount+2,0 mov word ptr fillcount,0 mov word ptr fillcount+2,0 les bx,dword ptr vs_parm1 mov word ptr blockaddr,bx mov word ptr blockaddr+2,es les bx,dword ptr vs_parm6 mov ax,es add bx,word ptr blockaddr adc ax,0 shl ax,12 add ax,word ptr blockaddr+2 mov word ptr currentaddr,bx mov word ptr currentaddr+2,ax mov word ptr filladdr,bx mov word ptr filladdr+2,ax les bx,dword ptr vs_parm2 mov word ptr blocksize,bx mov word ptr blocksize+2,es mov ax,es add bx,word ptr blockaddr adc ax,0 shl ax,12 add ax,word ptr blockaddr+2 mov word ptr blockend,bx mov word ptr blockend+2,ax cmp ax,word ptr currentaddr+2 ljb vs_error5 ja vs_getdatalen cmp bx,word ptr currentaddr ljbe vs_error5 vs_getdatalen: les bx,dword ptr vs_parm5 mov word ptr datalength,bx mov word ptr datalength+2,es mov ax,vs_parm4 mov filehandle,ax mov ax,vs_parm3 mov fileflag,ax or ax,ax jz vs_check mov fdoneflag,1 mov word ptr endaddr,0 mov word ptr endaddr+2,0 mov ax,word ptr blocksize sub ax,word ptr datalength mov ax,word ptr blocksize+2 sbb ax,word ptr datalength+2 jnc vs_catch mov ax,word ptr blocksize sub ax,min_blocksize mov ax,word ptr blocksize+2 sbb ax,0 jc vs_error2 vs_catch: call PVOICE_CATCHUP or ax,ax jnz vs_error3 jmp short vs_exit0 vs_check: mov ax,word ptr datalength+2 cmp ax,word ptr blocksize+2 ja vs_error1 jb vs_setend mov ax,word ptr datalength cmp ax,word ptr blocksize ja vs_error1 jb vs_setend mov ax,word ptr blockaddr mov word ptr endaddr,ax mov ax,word ptr blockaddr+2 mov word ptr endaddr+2,ax jmp short vs_exit0 vs_setend: les bx,dword ptr vs_parm5 mov ax,es add bx,word ptr blockaddr adc ax,0 shl ax,12 add ax,word ptr blockaddr+2 mov word ptr endaddr,bx mov word ptr endaddr+2,ax jmp short vs_exit0 vs_error1: mov ax,1 jmp short vs_exit vs_error2: mov ax,2 jmp short vs_exit vs_error3: mov ax,3 jmp short vs_exit vs_error5: mov ax,5 jmp short vs_exit vs_exit0: call startvoice sub ax,ax vs_exit: leave ret vs_parmlength PVOICE_START endp ;********************************************************************** ;* "Stop playback" procedure * ;********************************************************************** ;This is used when it is necessary to stop the playback before all ; data has been output to the speaker. ;This routine accepts no parameters and has no return information. public PVOICE_STOP PVOICE_STOP proc far call stopvoice sub ax,ax ret PVOICE_STOP endp ;********************************************************************** ;* "Get status" procedure * ;********************************************************************** ;This will supply certain status information about the operation of the ; voice playback routines. ;The first parameter is a far pointer to a dword which will receive the ; number of bytes which have already been output to the speaker. ;The second parameter is a far pointer to a dword which will receive the ; offset within the memory block of the byte that will be played next. ;The return value is a flag word in which the lowest two bits are ; significant: ;Bit # Meaning if 1 ;----- ------------ ; 0 playback is still in progress ; 1 unread data remains in file vst_parm1 equ [bp+10] ;length = 4 vst_parm2 equ [bp+6] ;length = 4 vst_parmlength equ 8 public PVOICE_STATUS PVOICE_STATUS proc far enter 0,0 les bx,vst_parm1 cli mov ax,word ptr datacount mov dx,word ptr datacount+2 mov es:[bx],ax mov es:[bx+2],dx les bx,vst_parm2 mov ax,word ptr currentaddr mov dx,word ptr currentaddr+2 sti shr dx,12 ;we can cheat here because we ; know it's incremented by 1000h units mov cx,word ptr blockaddr+2 shr cx,12 sub ax,word ptr blockaddr sbb dx,cx mov es:[bx],ax mov es:[bx+2],dx cli mov ax,fdoneflag shl ax,1 or ax,goflag sti leave ret vst_parmlength PVOICE_STATUS endp end