Programming Sound Cards

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Assembly Source File | 1995-01-01 | 19.0 KB | 504 lines

;══════════════════════════════════════════════════════════════════════════════ ; Play with Cxh/Bxh commands on SoundBlaster 16/16ASP (here 16/mono/unsigned) ; André Baresel (with some help from Craig Jackson) ;────────────────────────────────────────────────────────────────────────────── ; STATUS: DOES WORK ON SB16 ; ■ sound crackles after a while - dounno yet what it is ... ; (somethings going wrong in CONVERT_HALF...) ;────────────────────────────────────────────────────────────────────────────── ; Requirements: 80286, SoundBlaster 16/16ASP (see BASEADDR,DMA channel,IRQ number) ; Resolutions : 16-bit / 4..44khz ; Note : ■ We use only 8 bit data and convert it while playing into ; 16bit, look at CONVERT_HALF (at the end of this file) ; ■ To creat a 8 bit mono unsigned file do : ; "VOC2RAW TEST1.VOC /I" ; ; ■ DSP command 41h ... set DAC sample rate ; ■ DSP command D0h ... Halt Autoinit 8 bit DMA operation ; ■ DSP command D4h ... Continue Autoinit 8 bit DMA operation ; ■ DSP command B6h 00h ... autoinit 16 bit mono data with no sign ; .MODEL small .286 ; CONSTANTS ─────────────────────────────────────────────────────────────────── ; SoundBlaster SETUP BASEADDR EQU 0220h ;SoundBlaster base address DMAchannel EQU 5 ;SoundBlaster DMA channel IRQ7 EQU 15 ;SoundBlaster IRQ ; PIC MASKS FOR MASK/DEMASK IRQ PICANDMASK EQU 01111111b ;AND PIC mask for clear IRQ PICORMASK EQU 10000000b ;OR PIC mask for set IRQ ; DMA CONTROLLER REGISTERS (16bit) WRITEMASK EQU 0D4h ;WRITE MASK REGISTER WRITEMODE EQU 0D6h ;WRITE MODE REGISTER CLEARFLIPFLOP EQU 0D8h PAGE16_CHN EQU 08Bh ;PAGE REGISTER FOR DMAchannel 5 BASE16_CHN EQU 0C4h ;BASEADDRESS REGISTER DMA 5 COUNT16_CHN EQU 0C6h ;COUNT REGISTER DMAchannel 5 ; SAMPLERATE : RATE EQU 02AEDh ; = 10989 Hz ; DMA MODE WANTEDMODE EQU 01011000b ; singlemode, autoinit, readmode ; DMABuffer size : DMABUFFERSIZE EQU 8*1024 ;────────────────────────────────────────────────────────────────────────────── ; MACRO DEFINITIONs ;────────────────────────────────────────────────────────────────────────────── STARTUP MACRO ; MASM 5.x COMPATIBILITY __start: mov ax,DGROUP mov ds,ax mov bx,ss sub bx,ax shl bx,004h mov ss,ax add sp,bx ENDM WAITWRITE MACRO LOCAL loopWait,endloop ; Arguments : DX = Status port (BASEADDR+0Ch) ; Returns : n/a ; Destroys : AL push cx xor cx,cx ; need that for slow SBs ! loopWait: dec cx jz endloop in al,dx ; AL = WRITE COMMAND STATUS or al,al js loopWait ; Jump if bit7=1 - writing not allowed endloop: pop cx ENDM WAITREAD MACRO LOCAL loopWait,endloop ; Arguments : DX = Status port (normaly BASEADDR+0Eh) ; Returns : n/a ; Destroys : AL push cx xor cx,cx ; need that for slow SBs ! loopWait: dec cx jz endloop in al,dx ; AL = DATA AVAILABLE STATUS or al,al jns loopWait ; Jump if bit7=0 - no data available endloop: pop cx ENDM RESET_DSP MACRO local SBthere ; Arguments : n/a ; Returns : n/a ; Destroys : DX,AL mov dx,BASEADDR+06h mov al,1 out dx,al ; start DSP reset in al,dx in al,dx in al,dx in al,dx ; wait 3 µsec xor al,al out dx,al ; end DSP Reset add dx,08h ; dx = DSP DATA AVAILABLE WAITREAD sub dx,4 ; dx = DSP Read Data in al,dx cmp al,0aah ; if there is a SB then it returns 0AAh je SBthere jmp RESET_ERROR ; No SB - exit program SBthere: ENDM ;─── End of Macrodefinitions ────────────────────────────────────────────────── .STACK 100h .DATA ;────────────────────────────────────────────────────────────────────────────── ; Creat TEST1.INC with calling "VOC2RAW TEST1.VOC /I" or creat your own ; textfile with sampledata ; SAMPLEBUFFER LABEL BYTE INCLUDE TEST1.INC SAMPLEBUFFEREND LABEL BYTE PART db 0 information db 13,10,'DMASTP10.EXE - play 16bit mono data unsigned (that does only work on a' db 13,10,'SB16/SB16ASP)' db 13,10,'Pause playing with key "p" and continue it then with any key.' db 13,10,'Stop playing with <ESC>.',10,'$' memerror db 13,10,'Not enough memory to creat the DMA buffer','$' txtpart0 db 13,'playing part 0','$' txtpart1 db 13,'playing part 1','$' sberror db 13,10,'No SoundBlaster at this BASEADDR ! PROGRAM HALTED.','$' OLDInterruptSEG dw ? OLDInterruptOFS dw ? ; OFFSET AND PAGE FOR DMAC DMAbufferOFS dw ? DMAbufferPage db ? ; OFFSET AND SEGMENT FOR CPU ACCESS :) DMABufferDOSOFS dw ? DMABufferDOSSEG dw ? ; POSITION IN SAMPLEBUFFER WHILE CONVERTING position dw 0 SAMPLEBUFFERLENGTH = offset SAMPLEBUFFEREND - offset SAMPLEBUFFER ;────────────────────────────────────────────────────────────────────────────── .CODE STARTUP ; FIRST FREE NOT USED MEMORY : mov bx,ss mov ax,es sub bx,ax mov ax,sp add ax,15 shr ax,4 add bx,ax mov ah,04ah int 21h ; NOW ALLOCATE DMABUFFER mov bx,DMABUFFERSIZE*2/16 ; count of 16byte blocks for two buffers mov ah,48h int 21h jnc enoughmem mov dx,offset memerror mov ah,9 int 21h ; WRITE MSG 2 SCRN THAT THERE'S NOT ENOUGH MEM jmp return2dos enoughmem: ; AX = segment of DMA buffer / offset = 0 ;────────────────────────────────────────────────────────────────────────────── ; calculate page and offset for 16bit DMAcontroller : ; ; segment*16+offset=20bit memory location-> upper 3 bits *2 = page ; next 16 bits = offset ; last 1 bit - lost in space :) ; (because of word access) ;────────────────────────────────────────────────────────────────────────────── rol ax,4 mov bl,al and bl,00eh mov [DMAbufferPage],bl and al,0f1h ror ax,1 mov [DMABufferOFS],ax ;────────────────────────────────────────────────────────────────────────────── ; check for DMApage override : ; ... problem: DMA controller separates memory into 64KB pages, you can only ; transfer data is placed in one page - no page overrides are allowed ;────────────────────────────────────────────────────────────────────────────── ; To solve that : ; creat a DMA buffer with double size you want - if the first part is placed ; on a page border the second part is for sure not ;────────────────────────────────────────────────────────────────────────────── mov cx,DMABUFFERSIZE/2 ; we check for 128KB pages and DMABUFFERSIZE ; in WORDs neg ax ; ax = 65536 - ax (bytes left to DMA page border) cmp ax,cx ja nooverride ; USE SECOND PART : neg ax ; ax = offset first data add ax,cx ; use second part mov [DMABufferOFS],ax add [DMABufferPage],2 ; 2nd part is on next page ! nooverride: ;────────────────────────────────────────────────────────────────────────────── ; now fill the whole buffer with first words of data ; (2 times CALL CONVERT_HALF) ; ; but first - calculate the DOS SEG/OFS from the DMAPage/OFS (you know ; maybe we have to use second buffer half we don't know about ofs/seg yet) mov al,byte ptr [DMABufferOFS] and al,07h xor ah,ah shl ax,1 mov di,ax ; di = offset of DMAbuffer mov ax,[DMABufferOFS] and al,0f8h mov bl,[DMABufferPage] shr bl,1 or al,bl ror ax,3 mov es,ax ; es = segment of DMABuffer ;────────────────────────────────────────────────────────────────────────────── ; save these values for later CONVERT_HALF calls ; mov [DMABufferDOSOFS],di mov [DMABufferDOSSEG],ax xor ax,ax ; DS:SI - samples in dataseg ; ES:DI - DMABuffer ; fill the whole buffer with sample data CALL CONVERT_HALF CALL CONVERT_HALF ; NOW WE'RE READY FOR SB STUFF: RESET_DSP ; WRITE INFOMRATION TO SCREEN : mov dx,offset information mov ah,9 int 21h ; write program information to screen ; ENABLE SB SPEAKERS (for all SBs <SB16) mov dx,BASEADDR+00Ch ;DX = DSP Write Data or Command WAITWRITE mov al,0D1h ; AL = Enable speaker out dx,al ; Output: DSP Write Data or Command ; SETUP IRQ : xor ax,ax mov es,ax ; es to page 0 (Interrupt table) mov si,IRQ7*4 ; si = position in interrupt table ; DISABLE IRQ (if it was enabled somehow) in al,021h and al,PICANDMASK ; SET MASK REGISTER BIT TO DISABLE INTERRUPT out 021h,al ; CHANGE POINTER IN INTERRUPT TABLE mov ax,es:[si] mov [OLDInterruptOFS],ax ; save offset of old interupt vector for restoring mov ax,OFFSET OWN_IRQ mov es:[si],ax ; set offset of new interrupt routine mov ax,es:[si+2] mov [OLDInterruptSEG],ax ; save segment of old interupt vector for restoring mov ax,cs mov es:[si+2],ax ; set segment of new interrupt routine ; CHANGE PIC MASK : in al,021h and al,PICANDMASK ; CLEAR MASK REGISTER BIT TO ENABLE INTERRUPT out 021h,al mov cx,DMABUFFERsize/2-1 ; count of words we need :) ;────────────────────────────────────────────────────────────────────────────── ; Setup DMA-controller : ; ; 1st MASK DMA CHANNEL ; mov al,DMAchannel-4 ; channels 0..3 for the 2nd DMAC add al,4 out WRITEMASK,al ;────────────────────────────────────────────────────────────────────────────── ; 2nd CLEAR FLIPFLOP ; out CLEARFLIPFLOP,al ;────────────────────────────────────────────────────────────────────────────── ; 3rd WRITE TRANSFER MODE ; mov al,WANTEDMODE add al,DMAchannel-4 out WRITEMODE,al ;────────────────────────────────────────────────────────────────────────────── ; 4th WRITE PAGE NUMBER ; mov al,[DMAbufferPage] out PAGE16_CHN,al ;────────────────────────────────────────────────────────────────────────────── ; 5th WRITE BASEADDRESS ; mov ax,[DMABufferOFS] out BASE16_CHN,al mov al,ah out BASE16_CHN,al ;────────────────────────────────────────────────────────────────────────────── ; 6th WRITE BUFFERLENGTH (in words)-1 ; mov al,cl out COUNT16_CHN,al mov al,ch out COUNT16_CHN,al ;────────────────────────────────────────────────────────────────────────────── ; 7th DEMASK CHANNEL ; mov al,DMAchannel-4 out WRITEMASK,al ;────────────────────────────────────────────────────────────────────────────── ; Setup SoundBlaster : ; ; 1st SET SAMPLERATE ; mov dx,BASEADDR+00Ch ;DX = DSP Write Data or Command WAITWRITE mov al,041h ;AL = Set DAC Samplerate out dx,al WAITWRITE mov cx,RATE mov al,ch out dx,al WAITWRITE mov al,cl out dx,al ;────────────────────────────────────────────────────────────────────────────── ; 2nd USE 16bit MONO UNSIGNED MODE (DSPC B6h 00h) ; WAITWRITE mov al,0B6h ;AL = DMA DAC 16bit autoinit out dx,al WAITWRITE mov al,000h ;AL = mono unsigned data out dx,al mov cx,DMABUFFERSIZE/4-1 WAITWRITE mov al,cl ;AL = LOWER PART SAMPLELENGTH out dx,al WAITWRITE mov al,ch ;AL = HIGHER PART SAMPLELENGTH out dx,al ; TRANSFER STARTs.....NOW.... :) waitloop: mov ah,01 ;AH = Check for character function int 016h ; Interrupt: Keyboard jz waitloop ; wait for a key (sound in background) xor ah,ah ;Read character, flush keypress int 016h ; Interrupt: Keyboard cmp al,'p' ; check for pause key je pause ; ok cmp al,27 jne waitloop jmp exit pause: ; NOW PAUSE PLAYING: (on DSPv4.04 you can also use DSPC d4h,d0h!) mov dx,BASEADDR+00Ch ;DX = DSP Write Data or Command WAITWRITE mov al,0D5h out dx,al ; WAIT FOR ANY KEY ("<ANY> key?" shut up it's a stupid joke!) xor ah,ah ;Read character, flush keypress int 016h ; Interrupt: Keyboard mov dx,BASEADDR+00Ch ;DX = DSP Write Data or Command WAITWRITE mov al,0d6h out dx,al jmp waitloop exit: RESET_DSP ; RESTORE PIC MASK in al,021h or al,PICORMASK ;<-- SET REGISTER MASK BITS TO DISABLE out 021h,al ; RESTORE IRQ : xor ax,ax mov es,ax ; es to page 0 (Interrupt table) mov si,IRQ7*4 mov ax,[OLDInterruptOFS] mov es:[si],ax ; set old interrupt routine mov ax,[OLDInterruptSEG] mov es:[si+2],ax ; CLEAR KEYBUFFER mov ah,01 int 16h jz return2dos xor ah,ah ;Read character, flush keypress int 016h ; Interrupt: Keyboard ; TERMINATE EXE: return2dos: mov ax,04c00h int 21h ; display information if Soundblaster is not on this baseaddress RESET_ERROR: mov dx,offset sberror mov ah,9 int 21h ; text output jmp return2dos ;────────────────────────────────────────────────────────────────────────────── ; Our own IRQ for detecting buffer half SB currently plays ; It's generated by the SoundBlaster hardware ;────────────────────────────────────────────────────────────────────────────── OWN_IRQ: pusha mov dx,BASEADDR+00Fh ;DX = IRQ ACKNOWLEDGE 16Bit in al,dx mov ax,@data mov ds,ax mov dx,offset txtpart0 cmp [part],0 je notpart1 mov dx,offset txtpart1 notpart1: mov ah,9 int 21h ; text output call CONVERT_HALF ; fill next half... mov al,020h out 020h,al ;ACKNOWLEDGE HARDWARE INTERRUPT popa IRET ;────────────────────────────────────────────────────────────────────────────── ; Convert_half is for copying 8bit data from dataseg to dmabuffer with 16bit ; values (16bitvalue= 8bit value*256) ; one call - convert one buffer half ; next call - convert the other buffer half ; ... 2B Continued ... ;────────────────────────────────────────────────────────────────────────────── CONVERT_HALF: mov cx,DMABUFFERSIZE/2 ; half buffer size in bytes mov di,[DMABufferDOSOFS] cmp [part],0 je not2nd add di,cx not2nd: shr cx,1 ; count of words in half buffer mov ax,[DMABufferDOSSEG] mov es,ax mov si,offset samplebuffer add si,[position] xor al,al cloop: mov ah,ds:[si] stosw inc si cmp si,offset samplebuffer + samplebufferlength-2 ja samplerestart loop cloop jmp afterloop samplerestart: ; restart sample mov si,offset samplebuffer loop cloop afterloop: sub si,offset samplebuffer mov [position],si neg [part] inc [part] ; part = 1-part result: 0,1,0,1,0,1,... RET END __start