p0TP››››››            p0TP       ››››››            Several years ago, I bought MIDI MUSIC  SYSTEM  (MMS)  from››          Hybrid Arts, to complement the other Midi software I  use  on››          our ATARI 800 and 520ST. Included with MMS is a Basic program››          to convert ADVANCED MUSIC SYSTEM (AMS) files into MMS format.››          One reason I bought MMS was that I have  a  large  number  of››          very good AMS files and I wanted to  convert  them  and  hear››          them through our synthesizer. Unfortunately,  several  of  my››          better files were  too  big  for  the  converter  program  to››          handle. I decided to write  my  own  converter  program,  and››          chose Action! since it would  create  a  smaller  and  faster››          program.››››››            I pulled apart the original Basic program,  and  kept  only››          the AMS II to MMS portion (the basic program could do  AMS  I››          to MMS and AMS I to AMS II as well). By writing this program,››          I learned a fair bit about the format of the  files  used  in››          both AMS II  and  MMS,  plus  I  learned  a  bit  more  about››          programming in Action!››››››            You will notice a rather large table in the program, called››          AMSTEMPO. The original Basic program used  a  rather  complex››          formula using floating point numbers to convert  the  AMS  II››››››››››››››          tempo to the equivalent MMS tempo. I do not have the  Action!››          Toolkit package which adds floating point support, so  I  had››          to find an alternate method of doing the conversion. I  built››          the table which maps the  two  tempo  values  as  follows.  I››          search the table for an entry which is less than or equal  to››          the AMS II tempo. When one is found, the subscript  into  the››          table for  that  value  is  the  equivalent  MMS  tempo.  For››          example, if the AMS II tempo was 4171, the appropriate  entry››          in the table is in  the  entry  subscripted  by  16  (Action!››          arrays start with subscript 0, so the 17'th entry  (4171)  is››          at subscript location 16), so the equivalent MMS tempo is 16.››››››            Running AMS2MMS is quite simple. After loading it, you  are››          presented with  the  selection  screen.  You  can  choose  to››          convert a file by pressing 1, or quit execution  by  pressing››          2. Having selected to convert a file, you  are  prompted  for››          the file name. If you do not specify the device, the  default››          of drive 1 (D1:) will be added to the name  you  supply.  You››          are then prompted to enter the source disk.  At  this  point,››          the original file will be read. You will be prompted for  the››          MMS file name you want to use. There is no need to supply the››          file extender, since it will be set to .MUS for you. You will››          then be prompted to insert the  output  disk.  The  converted››          file will then be written. The output  process  will  not  be››          extremely fast, but a lot of processing is going  on  as  the››          file is being converted and written. Believe me, it  is  MUCH››››››››››››››          faster than the original Basic program. If the program cannot››          accurately convert the duration of a note, it so informs you,››          telling you the voice and measure where the problem occurred.››          Be sure to go back and fix the problem with MMS later, or the››          voices in the music file could go out of synch when played.››››››            I was able to use this program on all of my AMS  II  files,››          but there was one problem. It did not  support  the  dynamics››          (volume of the notes --- ppp (quiet) to FFF (loud)) that each››          note had in AMS II. I therefore decided to add this  feature.››          I put in a table which contains the equivalent velocities for››          the 8 different AMS II dynamics I support (ppp to FFF). These››          work fine on our Roland, but might not on your synthesizer if››          it does not support all the possible velocity values  between››          0 and 127. You should check into the velocity capabilities of››          your synthesizer, and change the table accordingly. The table››          is called MIDIVEL; update the  source  to  make  the  changes››          permanent, or override the defaults at startup time (you will››          be prompted for the appropriate velocity  values  -  enter  a››          number or just hit return to accept the default). Support  of››          velocity values makes the MMS  files  somewhat  bigger.  This››          could mean that some very large AMS files might  convert  but››          be too large to fit into MMS.››››››            The two versions of  my  program  are  called  AMS2MMS  and››››››››››››››          AMS2MMSV (V for Velocity).››››››            AMS2MMS and AMS2MMSV represented my most ambitious projects››          in Action! at the time. If the programs seem a bit cluttered,››          it is because my brain naturally works that way, plus  I  was››          converting a  Basic  program  which  was  not  written  in  a››          structured form in the first place. Even though they are  not››          elegant, they do at least work. Writing them  was  worth  the››          effort. Although the music files sounded quite  good  through››          AMS II, they sound much better through the synthesizer.››››››››››››››››››››››››››››››››››››››››