Chip 1997 March

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Assembly Source File | 1989-06-24 | 16.3 KB | 731 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 ;********************************************************************** ;* * ;* 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 record position in memory datacount dd 0 ;number of data bytes already recorded fwrtaddr dd 0 ;address of next byte to be written to disk fwrtcount dd 0 ;number of bytes already written to disk goflag dw 0 ;indicates whether recording is in progress fileflag dw 0 ;indicates whether data is written to a file filehandle dw 0 ;handle of file to receive voice data hookedflag dw 0 ;indicates whether the interrupt is hooked countfor_18hz dw 0 ;counter to determine when to call BIOS comaddr dw 0 ;the address of the COM port comlist dw 3FEh ;needed addresses of all COM ports dw 2FEh dw 3EEh dw 2EEh 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 popf ret stopvoice endp ;********************************************************************** ;* Interrupt service routine * ;********************************************************************** timer_tick proc far push ds push bx push es push ax push cx push dx mov ax,DGROUP mov ds,ax cmp goflag,0 je chain_exit les bx,currentaddr mov ah,es:[bx] mov dx,comaddr in al,dx rcl al,4 rcl ah,1 mov es:[bx],ah inc shiftcount and shiftcount,07h jnz exit_decide mov ax,es inc bx jnz check_wrap add ax,1000h check_wrap: cmp bx,word ptr blockend jne save_cur_addr cmp ax,word ptr blockend+2 jne save_cur_addr mov bx,word ptr blockaddr mov ax,word ptr blockaddr+2 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 dx pop cx pop ax pop es pop bx pop ds jmp cs:bios_timer_routine nochain_exit: mov al,20h out 20h,al pop dx 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 RVOICE_INIT RVOICE_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,RVOICE_CBREAK mov ax,seg RVOICE_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 RVOICE_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 RVOICE_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 RVOICE_CLEANUP RVOICE_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 RVOICE_CLEANUP endp ;********************************************************************** ;* Vector restore for Control-Break * ;********************************************************************** public RVOICE_CBREAK RVOICE_CBREAK proc far pusha push ds push es mov ax,DGROUP mov ds,ax call stopvoice call RVOICE_CLEANUP pop es pop ds popa stc ret RVOICE_CBREAK endp ;********************************************************************** ;* "File write catch-up" procedure * ;********************************************************************** ;This must be called frequently from the main program if file writing is ; being used and the length of the data to be recorded 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 writes ; new data to the file as it becomes available. ;There are no parameters. The return values are 0 for success 1 if there ; was no new data to write, or 2 if an error occurred while writing the file. vcat_temp1l equ [bp-4] ;current address from ISR vcat_temp1h equ [bp-2] vcat_temp2l equ [bp-8] ;<unused> vcat_temp2h equ [bp-6] ;the three stopping points: 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 RVOICE_CATCHUP RVOICE_CATCHUP proc far enter vcat_templength,0 ;should we even be doing this? cmp fileflag,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 ; three possible stopping points vcat_getgap: mov ax,vcat_temp1l sub ax,word ptr fwrtaddr mov vcat_temp3l,ax pushf mov ax,vcat_temp1h sub ax,word ptr fwrtaddr+2 sar ax,12 popf sbb ax,0 mov vcat_temp3h,ax vcat_getclearance: mov ax,word ptr blockend sub ax,word ptr fwrtaddr mov vcat_temp4l,ax pushf mov ax,word ptr blockend+2 sub ax,word ptr fwrtaddr+2 sar ax,12 popf sbb ax,0 mov vcat_temp4h,ax mov ax,word ptr fwrtaddr neg ax mov vcat_temp5l,ax mov word ptr vcat_temp5h,0 jnz vcat_cmp2 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_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_writefile vcat_fixcx: mov cx,0FE00h vcat_writefile: or cx,cx jz vcat_exit1 mov bx,filehandle push ds lds dx,fwrtaddr mov ah,40h int 21h pop ds jc vcat_error2 cmp ax,cx jne vcat_error2 ;update global varibles to show the current ; situation add word ptr fwrtcount,cx adc word ptr fwrtcount+2,0 add word ptr fwrtaddr,cx jnc vcat_fillwrap add word ptr fwrtaddr+2,1000h vcat_fillwrap: mov bx,word ptr blockend cmp bx,word ptr fwrtaddr jne vcat_exit0 mov ax,word ptr blockend+2 cmp ax,word ptr fwrtaddr+2 jne vcat_exit0 mov bx,word ptr blockaddr mov ax,word ptr blockaddr+2 mov word ptr fwrtaddr,bx mov word ptr fwrtaddr+2,ax jmp short vcat_exit0 ;return code exit points vcat_error2: mov ax,2 jmp short vcat_exit vcat_exit1: mov ax,1 jmp short vcat_exit ;normal exit point vcat_exit0: ;don't leave until at least one bit has been played ; if goflag is not 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 RVOICE_CATCHUP endp ;********************************************************************** ;* "Start recording" 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 written to ; a file. If it is 0, no file operations will be performed. ; 4 2 An open file handle. This is ignored if the flag word ; is 0. ; 5 2 A word containing the number of the COM port to be used ; for input (1 thru 4). ; 6 4 A dword indicating the offset within the memory block ; where recording is to begin. ;Return value Meaning ;------------ ------- ; 0 success ; 1 block size is too small (blocklen < 8192 and ; file write = yes) ; 2 voice recording is already in progress ; 3 a COM port number not within the range of 1 thru 4 ; was specified ; 4 starting position is not less than block length min_blocksize equ 8192 vs_parm1 equ [bp+20] ;length = 4 vs_parm2 equ [bp+16] ;length = 4 vs_parm3 equ [bp+14] ;length = 2 vs_parm4 equ [bp+12] ;length = 2 vs_parm5 equ [bp+10] ;length = 2 vs_parm6 equ [bp+6] ;length = 4 vs_parmlength equ 18 public RVOICE_START RVOICE_START proc far cmp goflag,0 je vs_begin mov ax,2 ret vs_parmlength vs_begin: enter 0,0 mov word ptr datacount,0 mov word ptr datacount+2,0 mov word ptr fwrtcount,0 mov word ptr fwrtcount+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 fwrtaddr,bx mov word ptr fwrtaddr+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 jb vs_error4 ja vs_gethandle cmp bx,word ptr currentaddr jbe vs_error4 vs_gethandle: mov ax,vs_parm4 mov filehandle,ax mov bx,vs_parm5 cmp bx,1 jb vs_error3 cmp bx,4 ja vs_error3 dec bx shl bx,1 lea ax,comlist add bx,ax mov ax,[bx] mov comaddr,ax mov ax,vs_parm3 mov fileflag,ax or ax,ax jz vs_exit0 mov ax,word ptr blocksize sub ax,min_blocksize mov ax,word ptr blocksize+2 sbb ax,0 jnc vs_exit0 mov ax,1 jmp short vs_exit vs_error3: mov ax,3 jmp short vs_exit vs_error4: mov ax,4 jmp short vs_exit vs_exit0: call startvoice sub ax,ax vs_exit: leave ret vs_parmlength RVOICE_START endp ;********************************************************************** ;* "Stop recording" procedure * ;********************************************************************** ;Call this to stop the voice recording operation. ;This routine accepts no parameters and has no return information. public RVOICE_STOP RVOICE_STOP proc far call stopvoice sub ax,ax ret RVOICE_STOP endp ;********************************************************************** ;* "Get status" procedure * ;********************************************************************** ;This will report the status of voice operations. ;The first parameter is a far pointer to a dword which will receive the ; number of bytes which have already been recorded. ;The second parameter is a far pointer to a dword which will receive a ; value indicating the offset within the memory block of the next byte ; to be filled by the recording operation. ;There is no return value. vst_parm1 equ [bp+10] ;length = 4 vst_parm2 equ [bp+6] ;length = 4 vst_parmlength equ 8 public RVOICE_STATUS RVOICE_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 sub ax,ax leave ret vst_parmlength RVOICE_STATUS endp end