HDD install patch for Illusion City, only 2Mb RAM required

Started by sangfroid, June 11, 2021, 06:48:00 PM

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sangfroid

These set of patches change some executables of Illusion City, version X68000, to run directly from a Hard Drive.
  • It runs directly from the HD, no subst.x, no 2HDSIM.x, nothing needed. It works perfectly with the original 2Mb of RAM, you no longer require 10Mb to store the images. It also saves and restores directly to HD, no extra steps needed.
  • It reproduces all the introduction, the existing 2HDSIM.x installation by Caius skips the second part after the logo (but it can b e fixed copying disk 7 files to it again).
  • Removed the subroutine that requested a new floppy disk and waited for a keypress, now it will totally skip that part.
  • The filenames were encoded in the ICITY68.X, MENU68.X and MTABLE.COM (this last one a very small binary), as templates of the form X:<filename>, the executable replaced that X by a A or B drive depending on in which drive it expected the file. This was replaced by .\filename, so it should work on any drive and directory supported by Human68k.
  • Some executables were compressed using JLZX 0.42, an in-place executable compressor. You can decompress and recompress it using ITA lzx 1.04 in http://retropc.net/x68000/software/tools/archiver/italzx/. This made the patched files sligthly smaller, and the patches are almost as big as the binaries because of that, a change in 20-30 bytes creates a totally different compressed file.
  • The patches are meant for these versions of the files:
    • Illusion City (Disk 1) MD5 sum 4762DCD2F87109289F2548900A2DFC20
    • MENU68.X MD5 sum FE779EEFE95163C54B5F83EFAD200205
    • ICITY68.X MD5 sum D6FA3B37C628B64389309F50DDD0DDEA
    • MTABLE.COM MD5 sum 5B7450AC4A70B354325930FFE7384EB9
  • The changes can surely be adapted easily to other versions, but these are the ones
  • I worked with.
  • This was tested on original hardware, a X68000 XVI, I played until the point you get a robot companion after the cutscenes showing the SIVA council. If you can, please test it more to check everything works as it should.
  • I also did a PC-98 version HDD patch if you prefer that version. I will post it in the PC98 forum when I have the files ready.
Installation:
  • Patch Disk 1 image with one of the above patches, I made .IPS and .BPS, there are many utilities supporting those.
  • Copy all the files from Disk 1 to Disk 7 to a directory in a HD drive
  • Optionally remove COMMAND.COM. CONFIG.SYS, HUMAN.SYS, and ICITY_0 to ICITY_6 (these were used to detect disk number)
  • Rename AUTOEXEC.BAT to !Start.bat or whatever you like.
  • Alternatively you can patch MENU68.X, ICITY68.X and MTABLE.COM separately and overwrite the original files.
Enjoy!


Illusion City X68000 HDD patch.zip

incrediblehark

Just tried this out and it works great! Thanks!

sangfroid

Quote from: incrediblehark on July 07, 2021, 04:05:20 PMJust tried this out and it works great! Thanks!
Thank you, it is good to know it is of use to somebody.

weidu

Thank you for sharing, I tested the MIDI , there is no sound and the machine freezes