ChaRleyTroniC's SUPERSONIC SYSTEM new version 1.1 a CRTC and Robot PD production The ChaRleyTroniC Supersonic System is a new program for composition of music on the CPC. The music can have three channels simultaneously as well as different envelopes, volume and noise. Seven octaves of notes are available. In addition, the Supersonic Compiler is supplied, which will transform a 16k music file into a (probably) smaller file which can be run from your own programs - either machine code or BASIC. THE MAIN PROGRAM (SONIC.BAS, SONIC.BIN) When you have run this program, the main editing screen will appear. At the bottom of the screen is the music display, made up of lines such as: 0005 C-3 00D0 E-3 00D0 G-3 00D0 The leftmost figure (here, 0005) is the beat number. You can have 1024 beats, numbered 0000 (the first to be played) to 1024, and they are played in order at the speed you want. The next part of the line is made up of three groups, each consisting of a note and its status. Each group represents a channel - you can have one note on each channel at once. The note is in the format note-octave. For example, above you see the note C-3. This means the note C in the third octave up - middle C. You can go from C-0 (the lowest) to C-7 (the highest). Finally in each group, there is a seemingly obscure hexadecimal number - in the above example, 00D0. This is made up of four separate values: volume envelope, tone envelope, starting volume and noise level. Volume envelope and tone envelope determine what the note sounds like - the subject is quite complicated, but there is an excellent explanation in your CPC's manual which I would refer you to. Starting volume is obvious - how loud the note is when it starts - and noise level is the level of "hiss" in the note. Each of these four can be varied from 0 to 15 - referred to in hexadecimal, i.e. 0-F (0-9 followed by A-F instead of 10-15). You can select a channel to edit by the left and right cursor keys. Similarly, you can move up and down notes by the up and down cursor keys. CTRL and the up cursor key will move you to beat 0000, or to move to a specified beat, press CTRL-B and input the beat number. To input a note, you should make sure that the right octave is selected (press CTRL-O to cycle through) and then play the note on the computer keyboard. It's arranged like a piano keyboard, viz: S D G H J 2 3 4 5 6 Key Z X C V B N M Q W E R T Y U I L * or < > ? Note C D E F G A B C D E F G A B C - next octave - (The raised keys are sharps/flats, indicated by a # - sharp - sign in the program). To change envelopes, volume or noise, press CTRL-E (volume envelope), CTRL-T (tone envelope), CTRL-V (volume) or CTRL-N (noise). These will alter the settings used for the next note. To change an existing note to the new settings, whilst retaining the old note, press COPY. When typing in music, ENTER leaves a beat (useful for rests, differing note lengths etc.) and CLR erases a note. When you've finished your music, at the end of each channel, press TAB - the "rpt" (repeat) legend will appear. Note that you cannot have "rpt" as the first item on a channel. When you want to hear your music, move to the right place and press CTRL-G (G for go). The music will start from your current position and will continue until you press a key. You can define envelopes before you RUN the program, or you can type in BASIC commands - such as ENV or ENT to define envelopes - using CTRL-C. Type CTRL-C, and you will be allowed to enter a BASIC command. Terminate with ENTER, and it will be obeyed and the program will continue. CTRL-R will change the speed at which the music plays - 4 being the fastest and 255 being deathly slow! There are four save/load keys. CTRL-S and CTRL-L save and load the music respectively, as a 16k binary file. CTRL-Z saves envelope definitions only, and CTRL-X reloads them. So you could create a file full of all the envelope definitions you use, and reload this for use in a tune. However, the envelope definitions are saved with the tune too. Finally, CTRL-U will let you cut the next 64 notes from your current position on the current channel into a store memory (1-16). These notes can be recalled and "attached" somewhere else in the music by CTRL-A. THE COMPILER (COMPILER.BAS, COMPILER.BIN) Note that the compiler must be on the same disc as the main program - or at least the file SONIC.BIN - for it to work. The compiler takes your saved (source) file from the main program, and produces a machine code file - usually more compact. This file can then be used in your own programs. The produced (destination) file is saved as a binary file beginning at address &8000 (decimal 32768). It is not relocatable. There are two CALLs to the routine which are possible: CALL &8000 - set up envelopes for the tune CALL &8003 - must be called every 1/50th of a second (e.g. at frame flyback). When called repeatedly (50 times a second), it plays the tune. You might also find the following firmware call useful: CALL &BCA7 - shuts up the sound chip From machine code, you should either work this into the main loop of the program (if it is synchronised to frame flyback, like most demos) - calling &8000 at the start - or construct some sort of interrupt (details in the Firmware Manual or The Ins and Outs of the Amstrad, publ. Melbourne House). From BASIC, you could CALL &8000 at the start of the program and then set up an EVERY 1 GOSUB whatever routine to CALL &8003 every 1/50th of the second. However, it's easier to write a short program to set up a machine code interrupt, and such a program is provided on the disc under the name INTER.BAS. This utilises the example music on the disc, HOLBERG.BIN (compiled). If you are using it from machine code, please note that none of the main set of registers (apart from SP!) are preserved, but the alternate set are unaltered. You are advised to PUSH any needed registers before CALLing &8003. COPYRIGHT This program is "Almost" Public Domain. I'm quite happy for individuals to copy it, but I don't want any PD libraries, BBSs, fanzines or what-have-you distributing it without my written permission. Those libraries and BBSs with permission are (22.05.91): Robot PD, Penguin Software, Demon PD, Technosoft PD, Arcade Fantasy BBS, Pussycat BBS European and other non-British libraries can use it without applying for permission. All queries, complaints, assassination attempts and free NeXT Workstations are appreciated at the following address: 2 Trent Road, Oakham, Rutland LE15 6HF, UK - or contact me on the Arcade Fantasy BBS, (0533) 376056 (mail Richard Fairhurst), all speeds up to V22bis, 8am-8pm, scrolling.