Instructions for using "proplayer.a", the stand-alone playroutine. ========================================================================== "proplayer" is a piece of code which is linked with your program and plays MED and OctaMED modules. "proplayer" contains the following routines: InitPlayer RemPlayer PlayModule ContModule StopPlayer SetTempo The arguments are passed in registers, and return values are returned in d0. These routines will trash registers d0-d1 and a0-a1. And now the descriptions of each one: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ InitPlayer -- initialize everything Before you can call the other functions, you must call this function. It allocates the audio channels, timer, serial port (if MIDI) etc... ARGUMENTS: none RETURNS: 0 if everything is ok, otherwise something failed. If something failed, you can still call the other routines - they just don't do anything. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ RemPlayer -- return everything back Call this when your program exits. It frees the audio channels, timer, serial port etc. ARGUMENTS: none RETURNS: nothing ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PlayModule -- start playing a module When you want to start playing, call this routine. ARGUMENTS: a0 = pointer to the module. See below for instructions how to obtain the pointer. RETURNS: nothing ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ StopPlayer -- stop playing ARGUMENTS: no arguments RETURNS: nothing ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ContModule -- continue playing This routine continues playing the module from the point it was stopped. ARGUMENTS: a0 = pointer to the module RETURNS: nothing ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ SetTempo -- set the playback tempo (This routine has not much use.) ARGUMENTS: d0 = new tempo (1 - 240) RETURNS: nothing ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "proplayer.a" is the source code of the music routine. It contains stuff that may be unnecessary for your purposes, just taking time and memory. There are some "switches" at the beginning of the source, that allow you to turn off features you don't need. They are: MIDI If only the Amiga audio channels are used, set this to 0. AUDDEV For some purposes, you may want to disable the code that allocates the audio channels using "audio.device", e.g. in a non-multitasking environment. Normally this should be 1. SYNTH If synth/hybrid sounds are not in use, this can be set to zero. CHECK This does some checkings to ensure that several values are correct (e.g. is the sample in memory, no Amiga effects on MIDI-tracks etc..). If you know that the song is correct, you can safely turn the checks off. RELVOL If you don't need the "relative volume", this can be zero. IFFMOCT If the song doesn't contain multi-octave IFF samples this can be zero. HOLD This turns off the hold/decay features. PLAYMMD0 If set, the play routine will also handle old MMD0 type modules. Useful for player programs. There's an additional flag, EASY. If set, the usage of the player routines is even more simplified, and you enter the module name into an INCBIN statement. There are two routines (_startmusic, _endmusic) you call to start and stop the music (the music can be started ONLY ONCE). The EASY option is suitable for demos etc. where only a single tune is required. "proplayer.a" also supports multi-modules. It defines a UWORD modnum (in assembler: _modnum). Set this variable to the number of the song you want to play before calling PlayModule (0 is the first, 1 is the second song etc..). For example: #include "proplayer.h" /* defines 'modnum' */ ... modnum = 1; /* Play the second module */ PlayModule(module); ... Assembler: xref _modnum xref _PlayModule ... move.w #1,_modnum lea _module,a0 jsr _PlayModule(pc) ... Timing ====== If you need vertical blanking timing, you can set VBLANK to 1 and CIAB to 0. In normal use this is not recommended (because of the 16 % difference in playing speed with NTSC and PAL Amigas), but if tight synchronization to vertical blanking (e.g. in most demos/games) is required, VBLANK should be used. For VBlank timing, the song has to be composed with primary tempo of about 33. The primary tempo cannot be changed with command F. Only the secondary tempo control can be used (command 9). Assembling ========== "proplayer.a" can be assembled by using A68k V2.61 (or later) or HiSoft Devpac 2 without need to make changes. Other assemblers may need some small changes to work correctly (mostly because the directives they support may be slightly different). The freely distributable assembler, A68k is available e.g. on Fish disk #314. If you're working on a linker environment (e.g. programming in C), you've to include the resulted "proplayer.o" in your .lnk-file. ========================================================================== And how to get some music? You have two ways to get the music: 1. Include the module in your final executable. 2. Save the module as a separate disk file and load it when needed (this is probably the best way if you have more than one song, and you don't want to use multi-modules). First I cover the first method: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Including the module in your final executable: The direct object file saving is removed now (you can still use the previous versions which support it, if you want). There's now another way to convert the song to an object file. There's a new utility, Objconv, which loads the module and dumps it into an object file. Here's an example how to use it: - Save the song as a module - Use Objconv e.g. objconv medmodule mod.o - Objconv requests the symbol name, enter "song" (without "'s), for example. - Now there's a file 'mod.o'. Link this file, and the file 'reloc.o' with your program. - In your program, you define the module: #include "proplayer.h" ... extern struct MMD0 far song; You must relocate the module before it's used. Do this only once! This is done by RelocModule(&song); RelocModule expects the argument in stack, so use __stdargs, if you've turned registerized parameters on. In assembler, you'd do exactly in the same way, except: xref _song xref _RelocModule xref _PlayModule ... (assuming all init stuff is here) lea _song,a0 move.l a0,-(sp) ;push into stack jsr _RelocModule(pc) addq.l #4,sp ;reset stack pointer lea _song,a0 ;this is passed in register a0 jsr _PlayModule ... Note: if you've got an assembler that supports 'incbin' directive or equivalent, you can use it instead of Objconv. Relocation is required in any case. And the second method (loading modules from disk): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ File "loadmod.a" contains three routines: LoadModule UnLoadModule RelocModule You usually need only the first two of them. RelocModule is used by LoadModule. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ LoadModule -- loads a module from disk This function loads a module from disk. Note that relocation is done automatically, so you must not RelocModule() a module obtained by using this routine. ARGUMENTS: a0 = pointer to file name RETURNS: d0 = pointer to the module, if something failed: 0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ UnLoadModule -- free the module from memory Frees the module. Remember to StopPlayer() before you unload the module that is currently playing. Also remember to free all modules you've loaded before you exit the program. ARGUMENTS: a0 = pointer to the module (may be 0) RETURNS: nothing ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ========================================================================== REMEMBER: All functions expect the arguments in registers (except RelocModule() from reloc.o). This is automatically (??) handled by you when you program in assembler, but it is not automatically handled when you're programming in C. If you have Lattice/SAS C V5.xx, this is done automatically if you include "proplayer.h" in all your code modules which call proplayer. If you have a compiler which doesn't support argument passing in registers, then you have to write the stub routines in assembler. See also the small example sources. ========================================================================== pro8player.a ~~~~~~~~~~~~ "pro8player.a" is the play-routine for OctaMED 5 - 8 channel songs. This can be used exactly in the same way as "proplayer.a". The functions just have slightly different names: InitPlayer8 RemPlayer8 PlayModule8 ContModule8 StopPlayer8 modnum8 Note that this player have some restrictions, as opposed to "proplayer.a". They're listed in OctaMED documents. It also takes LOTS of processor time, depending on how many splitted channels there are. You can use the same RelocModule() and (Un)LoadModule() routines with 5 - 8 channel songs. ==========================================================================