Power DOS 1996 July

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Assembly Source File | 1996-04-18 | 19.5 KB | 624 lines

; -------------------------------------------------------------------------- ; THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY ; KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE ; IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR ; PURPOSE. ; ; You have a royalty-free right to use, modify, reproduce and ; distribute the Sample Files (and/or any modified version) in ; any way you find useful, provided that you agree that ; Creative has no warranty obligations or liability for any Sample Files. ;---------------------------------------------------------------------------- ; --------------------------------------------------------------------------- ; Program: Sound Blaster 16 MIDI Utilities ; Filename: MIDIUTIL.ASM ; Author: Scott E. Sindorf ; Language: Borland TASM ; Date: 30 Jun 93 ; ; Copyright (c) 1993-1996 Creative Labs, Inc. ; --------------------------------------------------------------------------- SBMIDI equ 0 MPU401 equ 1 ; MPU-401 definitions MPU401_RESET equ 0ffh MPU401_UART equ 03fh MPU401_CMDOK equ 0feh MPU401_OK2WR equ 040h MPU401_OK2RD equ 080h ; SB-MIDI definitions MIDI_IN_P equ 30h ; MIDI read (polling mode) MIDI_IN_I equ 31h ; MIDI read (interrupt mode) MIDI_UART_P equ 34h ; MIDI UART mode (polling mode) MIDI_UART_I equ 35h ; MIDI UART mode (interrupt mode) MIDI_UART_TS_P equ 36h ; same as 0x34 with timestamp MIDI_UART_TS_I equ 37h ; same as 0x35 with timestamp MIDI_OUT_P equ 38h ; MIDI write (polling mode) ; SB Port definitions DSP_RST equ 06h ; DSP reset port DSP_RD_ST equ 0eh ; DSP read buffer status port DSP_RD equ 0ah ; DSP read port DSP_WR_ST equ 0ch ; DSP write buffer status port DSP_WR equ 0ch ; DSP write port DSP_OK2WR equ 80h DSP_OK2RD equ 80h ON equ 1 OFF equ 0 ERROR equ -1 OK equ 0 .MODEL small, C INCLUDE SBCUTILS.INC PUBLIC Write_MPU401_Cmd PUBLIC Write_MPU401_Data PUBLIC Write_SBMIDI_Data PUBLIC Read_MPU401_Data PUBLIC Read_SBMIDI_Data PUBLIC Send_MIDI_Message PUBLIC Set_MIDI_Vol PUBLIC Set_MIDI_Notes_Off PUBLIC Set_MIDI_Pitch_Bend PUBLIC Reset_MPU401 PUBLIC Set_UART_Mode PUBLIC Detect_MIDI PUBLIC Init_MIDI PUBLIC Exit_MIDI PUBLIC MIDIType ;----------------------------------------------------------------------------- ; DATA ;----------------------------------------------------------------------------- .DATA MIDIType db MPU401 ; MIDI type to use flag msg db 3 dup(?) ;----------------------------------------------------------------------------- ; CODE ;----------------------------------------------------------------------------- .CODE ;------------------------------------------------------------------------ ; WRITE_MPU401_CMD: sends a command to the MPU401 port. ; ; Input: command - command byte ; ; Output: none ;------------------------------------------------------------------------ Write_MPU401_Cmd PROC command:BYTE push ax push dx mov dx, blastInfo.midiPort ; MPU-401 base I/O address inc dx ; status port Busy1: in al, dx ; read status port test al, MPU401_OK2WR ; ready for output? jnz Busy1 ; nope mov al, command ; get command byte out dx, al ; write command byte pop dx pop ax ret Write_MPU401_Cmd ENDP ;------------------------------------------------------------------------ ; WRITE_MPU401_DATA: sends a data byte to the MPU401 port. ; ; Input: data - data byte ; ; Output: none ;------------------------------------------------------------------------ Write_MPU401_Data PROC data:BYTE push ax push dx mov dx, blastInfo.midiPort ; MPU-401 base I/O address inc dx ; status port Busy2: in al, dx ; read status port test al, MPU401_OK2WR ; ready for output? jnz Busy2 ; nope mov al, data ; get data byte dec dx ; data port out dx, al ; write data byte pop dx pop ax ret Write_MPU401_Data ENDP ;------------------------------------------------------------------------ ; WRITE_SBMIDI_DATA: sends a byte to the Sound Blaster MIDI port. ; ; Input: data - data byte ; ; Output: none ;------------------------------------------------------------------------ Write_SBMIDI_Data PROC data:BYTE push ax push dx mov dx, blastInfo.baseAddr ; SB base I/O address add dl, DSP_WR_ST ; status port / data port Busy3: in al, dx ; read status port test al, DSP_OK2WR ; ready for output? jnz Busy3 ; nope mov al, MIDI_OUT_P ; "MIDI out" command out dx, al ; send "MIDI out" command Busy4: in al, dx ; read status port test al, DSP_OK2WR ; ready for output? jnz Busy4 ; nope mov al, data ; get data byte out dx, al ; write data byte pop dx pop ax ret Write_SBMIDI_Data ENDP ;------------------------------------------------------------------------ ; READ_MPU401_DATA: reads a byte from the MPU401 port. ; ; Input: none ; ; Output: AL - data byte ;------------------------------------------------------------------------ Read_MPU401_Data PROC push dx mov dx, blastInfo.midiPort ; MPU-401 base I/O address inc dx ; status port Busy5: in al, dx ; read status port test al, MPU401_OK2RD ; MIDI data available? jnz Busy5 ; nope dec dx ; data port in al, dx ; read data byte / clear MIDI int. pop dx ret Read_MPU401_Data ENDP ;------------------------------------------------------------------------ ; READ_SBMIDI_DATA: reads a byte from the Sound Blaster MIDI port. ; ; Input: none ; ; Output: AL - data byte ;------------------------------------------------------------------------ Read_SBMIDI_Data PROC push dx mov dx, blastInfo.baseAddr ; SB base I/O address add dl, DSP_WR_ST ; status port / data port Busy6: in al, dx ; read status port test al, DSP_OK2WR ; ready for output? jnz Busy6 ; nope mov al, MIDI_IN_P ; "MIDI in" command out dx, al ; send "MIDI in" command mov dx, blastInfo.baseAddr ; SB base I/O address add dl, DSP_RD_ST ; status port Busy7: in al, dx ; read status port test al, DSP_OK2RD ; MIDI data available? jz Busy7 ; nope mov dx, blastInfo.baseAddr ; SB base I/O address add dl, DSP_RD ; data port in al, dx ; read data byte mov ah, al ; save it mov dx, blastInfo.baseAddr ; SB base I/O address add dl, DSP_WR_ST ; status port / data port Busy8: in al, dx ; read status port test al, DSP_OK2WR ; ready for output? jnz Busy8 ; nope mov al, MIDI_IN_P ; "MIDI in" command out dx, al ; turn off "MIDI in" command mov al, ah ; retrieve data byte read pop dx ret Read_SBMIDI_Data ENDP ;------------------------------------------------------------------------ ; SEND_MIDI_MESSAGE: Sends a MIDI message to port ; ; Input: message - MIDI message to send ; size - length of message ; ; Output: none ;------------------------------------------------------------------------ Send_MIDI_Message PROC message:FAR PTR BYTE, msgSize:WORD push cx push si push es mov cx, msgSize mov si, SEG message mov es, si mov si, OFFSET message cld ; count up cmp MIDIType, MPU401 ; are we using MPU-401? jne WrSBMIDI ; nope WrMPU401: push es:[si] ; get byte call Write_MPU401_Data ; send it via MPU-401 add sp, 2 ; cleanup stack inc si ; next byte in message loop WrMPU401 ; do it again jmp short ExitSend WrSBMIDI: push es:[si] ; get byte call Write_SBMIDI_Data ; send it via SBMIDI add sp, 2 ; cleanup stack inc si ; next byte in message loop WrSBMIDI ; do it again ExitSend: pop es pop si pop cx ret Send_MIDI_Message ENDP ;------------------------------------------------------------------------ ; SET_MIDI_VOL: Sets the global volume on the requested channel ; ; Input: channel - set volume on this channel (1 to 16) ; volume - set channel to this volume (0 to 127) ; ; Output: none ; ; note: if inputs are out of range then no action occurs ;------------------------------------------------------------------------ Set_MIDI_Vol PROC channel:BYTE, volume:BYTE push ax cmp channel, 16 ; test channel number for ja BadVal1 ; proper range cmp channel, 0 jbe BadVal1 cmp volume, 127 ; test volume value for ja BadVal1 ; proper range cmp volume, 0 jb BadVal1 mov al, channel ; create MIDI message mov [msg], al add [msg], 0b0h dec [msg] mov [msg + 1], 7 mov al, volume mov [msg + 2], al push 3 ; get message size push SEG msg ; get MIDI message pointer push OFFSET msg call Send_MIDI_Message add sp, 6 ; cleanup stack BadVal1: pop ax ret Set_MIDI_Vol ENDP ;------------------------------------------------------------------------ ; SET_MIDI_NOTES_OFF: Turns off all notes on the given channel ; ; Input: channel - turns off all notes on this channel (1 to 16) ; ; Output: none ; ; note: if channel is out of range then no action occurs ;------------------------------------------------------------------------ Set_MIDI_Notes_Off PROC channel:BYTE push ax cmp channel, 16 ; test channel number for ja BadVal2 ; proper range cmp channel, 0 jbe BadVal2 mov al, channel ; create MIDI message mov [msg], al add [msg], 0b0h dec [msg] mov [msg + 1], 7bh mov [msg + 2], 0 push 3 ; get message size push SEG msg ; get MIDI message pointer push OFFSET msg call Send_MIDI_Message add sp, 6 ; cleanup stack BadVal2: pop ax ret Set_MIDI_Notes_Off ENDP ;------------------------------------------------------------------------ ; SET_MIDI_PITCH_BEND: Sets pitch bend (0 = OFF). ; ; Input: channel - sets pitch bend on this channel (1 to 16) ; bend - pitch bend value (-8192 to 8191) ; Input: AH - sets pitch bend on this channel (1 to 16) ; BX - pitch bend value (-8192 to 8191) ; ; Output: none ; ; note: if inputs are out of range then no action occurs ;------------------------------------------------------------------------ Set_MIDI_Pitch_Bend PROC channel:BYTE, bend:WORD push ax cmp channel, 16 ; test channel number for ja BadVal3 ; proper range cmp channel, 0 jbe BadVal3 cmp bend, 8191 ; test volume value for jg BadVal3 ; proper range cmp bend, -8192 js BadVal3 mov al, channel ; create MIDI message mov [msg], al add [msg], 0e0h dec [msg] mov ax, bend ; get bend value add ax, 8192 ; make it two 7 bit values shl ax, 1 shr al, 1 mov WORD PTR [msg + 1], ax push 3 ; get message size push SEG msg ; get MIDI message pointer push OFFSET msg call Send_MIDI_Message add sp, 6 ; cleanup stack BadVal3: pop ax ret Set_MIDI_Pitch_Bend ENDP ;------------------------------------------------------------------------ ; RESET_MPU401: resets the MPU401 port. ; ; Input: none ; ; Output: AX - (0 = OK, -1 = ERROR) ; ; note: Error will occur if UART mode is not turned off first. ;------------------------------------------------------------------------ Reset_MPU401 PROC push cx push MPU401_RESET ; Reset command call Write_MPU401_Cmd ; send it via MPU-401 add sp, 2 ; cleanup stack sub cx, cx ; Maximum of 65536 tries Empty1: call Read_MPU401_Data cmp al, MPU401_CMDOK ; successful reset? je ResetOK ; success! loop Empty1 ; try again mov ax, ERROR jmp short ExitReset ResetOK: mov ax, OK ExitReset: pop cx ret Reset_MPU401 ENDP ;------------------------------------------------------------------------ ; SET_UART_MODE: puts the MPU401 port in UART mode. ; ; Input: state - ON or OFF (Reset will return error if UART mode is on ; when reset occurs) ; ; Output: AX - (0 = OK, -1 = ERROR) ;------------------------------------------------------------------------ Set_UART_Mode PROC state:WORD push cx cmp state, OFF ; turn UART mode off? je TurnOff ; yes push MPU401_UART ; UART mode command call Write_MPU401_Cmd ; send it via MPU-401 add sp, 2 ; cleanup stack sub cx, cx ; Maximum of 65536 tries Empty2: call Read_MPU401_Data cmp al, MPU401_CMDOK ; successful mode change? je UARTModeOK ; success! loop Empty2 ; try again mov ax, ERROR jmp short ExitSetUART TurnOff: push MPU401_RESET ; turn off UART mode with reset call Write_MPU401_Cmd ; (will not return acknowledge) add sp, 2 ; cleanup stack UARTModeOK: mov ax, OK ExitSetUART: pop cx ret Set_UART_Mode ENDP ;------------------------------------------------------------------------ ; DETECT_MIDI: Detects the presence of the MPU-401 port or the SBMIDI ; port. ; ; Input: none ; ; Output: AX - (0 = OK, -1 = ERROR) ;------------------------------------------------------------------------ Detect_MIDI PROC push dx cmp MIDIType, MPU401 ; are we using MPU-401? jne DtSBMIDI ; nope mov dx, blastInfo.midiPort ; MPU-401 base I/O address inc dx ; status port in al, dx ; read status port test al, MPU401_OK2WR ; ready for output? jnz DtError ; nope push OFF ; turn off UART mode just in case call Set_UART_Mode add sp, 2 ; cleanup stack call Reset_MPU401 ; reset the MPU-401 port or ax, ax ; was reset OK? jnz DtError ; nope mov ax, OK jmp short DtExit DtSBMIDI: call DSPReset ; try to reset DSP jmp short DtExit DtError: mov ax, ERROR DtExit: pop dx ret Detect_MIDI ENDP ;------------------------------------------------------------------------ ; INIT_MIDI: Initializes the MIDI port. If MPU-401 port then reset ; the port and select UART mode. For either MPU-401 or ; SBMIDI ports set all master volumes to 100, turn off all ; notes, and reset all pitch bends. ; ; Input: none ; ; Output: AX - (0 = OK, -1 = ERROR) ;------------------------------------------------------------------------ Init_MIDI PROC push cx cmp MIDIType, MPU401 ; are we using MPU-401? jne ItSBMIDI ; nope call Reset_MPU401 ; reset MPU401 port or ax, ax ; was reset OK? jnz ItError ; nope push ON ; turn on UART mode call Set_UART_Mode add sp, 2 ; cleanup stack or ax, ax ; was mode change OK? jnz ItError ; nope ItSBMIDI: mov cx, 16 ; for sixteen channels ItNextChl: push 100 ; set volume to 100 (GM default) push cx call Set_MIDI_Vol call Set_MIDI_Notes_Off ; turn off all notes add sp, 4 ; cleanup stack push 0 ; clear all pitch bends push cx call Set_MIDI_Pitch_Bend add sp, 4 ; cleanup stack loop ItNextChl ; do next channel mov ax, OK jmp short ItExit ItError: mov ax, ERROR ItExit: pop cx ret Init_MIDI ENDP ;------------------------------------------------------------------------ ; EXIT_MIDI: Terminates MIDI driver by turning off all notes (and ; turning off UART mode if using MPU-401 port). ; ; Input: none ; ; Output: none ;------------------------------------------------------------------------ Exit_MIDI PROC push cx mov cx, 16 ; for sixteen channels ExNextChl: push cx call Set_MIDI_Notes_Off ; turn off all notes add sp, 2 ; cleanup stack loop ExNextChl ; do next channel cmp MIDIType, MPU401 ; are we using MPU-401? jne ExExit ; nope push OFF ; turn off UART mode call Set_UART_Mode add sp, 2 ; cleanup stack ExExit: pop cx ret Exit_MIDI ENDP END