Multiface owners who enjoy looking for pokes must have noticed that the files are saved out to tape or disk in a compressed form (check out the screen contortions when saving). This is economical as far as loading time and disk tape space are concerned, but means that you can't look through the game code. Until now. that is... After many sleepless nights spent working out how the Multiface compresses its code, here is an RSX (yes, I've been reading the series) routine, |EXPAND. It will restore your squashed up game files to their original glory. Multiface files are saved out with the suffixes 1,2,3 etc to denote the memory block they belong to. 1 is 0000 to 3FFF, 2 is 4000 to 7FFF etc. Load the file you wish to examine at (say) &4000 then use the instruction |EXPAND,&4000 to reconstitute the original code using the memory space 4000 to 7FFF. The extension &4000 tells the prog where the compressed code starts. - Type in EXPAND and save it.
- Run the program.
- Lower memory top : MEMORY &3FFF
- Load MULTIFACE code : LOAD "GAME1 ",&4000
- Expand to original : |EXPAND,&4000
- Save restored code : SAVE "NEWGAME1 ".&4000,&4000
The code can then be loaded into a monitor disassembler or a utility for examination. Just a little idea you may like to try: If you make 2 copies of the same game, one just before, and one just after losing a life. Then load and expand the first at &2000 (|EXPAND,&2000) and the second at &6000 (IEXPAND.&6000). You
can then get the computer to search through the two sets of code and compare them, this will tell you where the differences are, ie. the address where the lives are stored. AA | ★ AMSTRAD CPC ★ DOWNLOAD ★ |
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CPCrulez[Content Management System] v8.7-desktop/c
Page créée en 547 millisecondes et consultée 937 foisL'Amstrad CPC est une machine 8 bits à base d'un Z80 à 4MHz. Le premier de la gamme fut le CPC 464 en 1984, équipé d'un lecteur de cassettes intégré il se plaçait en concurrent du Commodore C64 beaucoup plus compliqué à utiliser et plus cher. Ce fut un réel succès et sorti cette même années le CPC 664 équipé d'un lecteur de disquettes trois pouces intégré. Sa vie fut de courte durée puisqu'en 1985 il fut remplacé par le CPC 6128 qui était plus compact, plus soigné et surtout qui avait 128Ko de RAM au lieu de 64Ko. |
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