MEGA16
This page was last modified 09:02, 16 May 2020 by Mars2000you. Based on work by Gdx and Rderooy.

Contents

Description

MEGA16 is a ROM loader developed by Mikasen that can only run MegaROM with pages of 16kB using a MSX Memory Mapper.

The latest version is "Release 8". It is available here (Japanese mirror) or here (English mirror). We can improve ROM support of release 8 with the the patch below.

Environment

  • Computer MSX2/2+/Turbo R with 256kB or more
  • MSX-DOS1/2
  • Rom dumps (You can use MGSAVE to make a dump)

Use

Enter the following command under MSX-DOS.

mega16 [<options> ]<Filename.ext> [<options>]

Options:

  • -Sps[-ss] specifies the slot of the RAM with Memory Mapper. ps is a number between 0 and 3 to specify the primary slot. ss specifies the secondary slot. By default the main Memory Mapper is selected, and You will need a larger Mapper than the ROM for it to work.
  • -Z to run the ROM in Z80 Mode
  • -R to run the ROM R800 Rom
  • -D to run the ROM R800 Ram
  • -L Advanced Finding of page change addresses
  • -Wt Adds a wait time for a page change. t is a number between 0 and 255. (This option seems useless.)

Compatibility list

Title Compatibility Remarks
A Ressha de Ikou - Take the A-train Doesn't work Original cartridge has a SRAM of 2kB.
Abu Simbel Profanation Works Tape converted to ROM (crc32=ddbc1f28). Use -Z option on Turbo R.
AcroJet Doesn't work Runs but crashes quickly.
Aleste See remark Works with the patched release 8. -Z option is recommended on Turbo R.
Aliens Alien 2 Works
Aliens Alien 2 (Zemina) See remark Works if we replace the byte "80" by "70" at offset address 000Ch in Rom.
Adventure Kid Works Use -Z option on Turbo R. Game extracted from 4 Pak All Action cartridge and converted for MSX by a unknown user.
Andorogynus Han Seimei Senki See remark Works without graphic glitches if we replace all three bytes "32 FF 77" by "32 00 70" in Rom.
Aoki Ookami to Shiroki Mejika - Genghis Khan Doesn't work Original cartridge have a SRAM
Arctic - Active Rail Playing Doesn't work
Craze Works Option -Z is recommended on Turbo R.
Cross Blaim See remark Works only if we replace all three bytes "32 45 40" by "32 00 70", "32 FF BF" by "32 00 70" and "3E CD 32 35 40 21 40 40 77 BE 28 20" by "00 00 00 00 00 00 00 00 00 00 00 00.
Daisenryaku MSX2 Playable Can't save because the original cartridge have a SRAM.
Devil Zone See remark Works without graphic glitches with the patched release 8.
Dungeon Hunter Need a light gun and CRT monitor.
Dynamite Bowl Works
Family Stadium Pro Yakyuu Pennant Race Works
Fantasy Zone II Opa-Opa no Nami See remark Works only if we replace all three bytes "32 F8 77" by "32 00 70". Use -Z option on Turbo R.
Gakuen Monogatari - High School Story Doesn't work
Gall Force Defense of Chaos Works
Gangjeol Robocop See remark Original Rom works with a generic mapper 8k but you can convert it to mapper ASCII 16k with following method: Replace all "32 00 60" by "32 00 00", all "32 00 80" by "32 00 70" and all "32 00 A0" by "32 00 00". Replace also "F5 3E 02" by "F5 3E 01" and "BC D0 3E 06" by "BC D0 3E 03".
Garakuta Works Load/Save not supported, except perhaps if we run the game from a floppy drive (without other disk interface).
Girly block Works
Golvellius Works
Hacker Works
Harryfox Yuki no Maouhen Doesn't work
Harryfox Special Doesn't work Original cartridge has a SRAM of 2kB.
Hydlide II Shine of Darkness Works Can't keep save because original cartridge has a SRAM of 2kB.
Higemaru Makaijima Nana-tsu no Shima Daibouken Works Zemina version also works.
Hole in One Special Works
Ikari See remark Works only if we replace all three bytes "32 FF 67" by "32 00 60". Use -Z option on Turbo R.
Inemuriryuu Asada Tetsuya no A-kyuu Mahjong Works
Ishtar no Fukkatsu - The Return of Ishtar Works
Jagur 5 See remark Works with the patched release 8.
Jansei Playable Works but we can save a game because the original cartridge has a SRAM.
Kempelen chess Doesn't work
King's Knight Works Option -Z is recommended on Turbo R.
Knither Special Works Option -Z is recommended on Turbo R.
Koronis Rift Doesn't work Runs but crashes the game starts.
Magnum Kiki Ippatsu Empire City See remark Works fine if we replace the two bytes "FF 77" by "00 70" at offset address 030B3h.
Malaya no Hihou Works English version works too.
Meikyuu he no Tobira - Gate of Labyrinth Doesn't work
Meikyuu Shinwa - Eggerland 2 See remark Works only when the memory mapper is in slot 1, otherwise the game works if we replace the byte "01" at offset address 0087h by the slot number (F000SSPP format for secondary slot) in which the memory mapper is located. Option -Z is recommended on Turbo R.
Nihongo Word processor MSX-Write
Ogre Works
Penguin-kun Wars 2 Doesn't work
Professional Mahjong Gokuu Doesn't work Original cartridge has a SRAM
R-Type Works Use 16K mapper specific.
Robo Wrest 2001 Works -Z option is recommended on Turbo R. Zemina version doesn't work.
Romancia for MSX1 See remark Works if we replace the six bytes "00 00 00 00 00 00" by "3E 02 32 00 70 C9" at offset addresses 00007h and 18007h, replace also "21 00 70 36 02" by "F5 CD 0A 40 F1" at 0070Dh and 1870Dh. -Z option is recommended on Turbo R.
Romancia for MSX2 Works -Z option is recommended on Turbo R.
Shanghai Works
Strategic Mars See remark Works fine if we replace the byte "77" by "00" at offset address 00039h and using the laster patched release 8. -Z option is recommended on Turbo R.
Super Daisenryaku Doesn't work Original cartridge has a SRAM
Super Games World 126 (Screen Software) Works ROM of 2048kB! (Needs a Memory Mapper of 4096kB).
Super Games 90 Doesn't work I/O port 077h is used to change the pages
Super Lode Runner See remark Works if we replace the bytes "00 00" by "10 40" at offset address 0002h, "10 80" by "00 00" at 000Ah, "00 1E 80 0A 00 97 20 DD 11 EF 0C 00 81 00 2A 80 14 00 41 EF DD 11 28 11 29 00 00 00 00 00 00 00 00 00 00" by "CD 38 01 0F 0F E6 03 4F 06 00 21 C1 FC 09 7E E6 80 B1 4F 23 23 23 23 7E E6 0C B1 26 80 CD 24" at 0010h, "80" by "70" at 08130h and all "32 00 00" by "32 00 70".
Super Pierrot (Nidecom) Works
Super Rambo Special Works Use -Z option on Turbo R.
The Apeman Strikes Again Works Tape converted to ROM (crc32=e5b36770). -Z option recommended on Turbo R.
The Black Onyx II Search for the Fire Crystal Works Use -L option, and -Z on Turbo R. Needs cassette tape to save.
The Cockpit Works Option -Z is recommended on Turbo R
The Light Corridor Doesn't work (Does not work on some MSX)
Tumego 120 Doesn't work
Vaxol Heavy Armed Storm Vehicle See remark Works with the patched release 8.
Victorious Nine II Koukou Yakyuu Hen See remark Works if we replace the all three bytes "32 FF 77" by "32 00 70", all "E5 21 FF 77 36 06 E1" by "F5 3E 06 32 00 70 F1" and the "E5 21 FF 77 36 02 E1" by "F5 3E 02 32 00 70 F1".
Volfoss to 5-nin no Akuma See remark Works with the patched release 8.
Wild Puzzle See remark Works if we replace the all three bytes "32 FF 77" by "32 00 70". Replace also the bytes "10" by "0D" at offset address 0002h and "00 00 00" by "31 8E F0" at 000Dh. (Needs a Memory Mapper of 2048 or more.)
Woody Poco See remark Works only if we replace the bytes "21 01 40 7E 2F 77 BE 28 0D" by "00 00 00 00 00 00 00 00 00".
Xevious Fardraut Saga Works Use -Z option on Turbo R
Zanac Ex Works Use -Z option on Turbo R
Zoids Chuuou Tairiku no Tatakai See remark Works if we replace the all two bytes "F8 77" by "00 70".


Note: This list must contain only ROMs with mapper using pages of 16K.

How to improve ROM support for release 8

Open the file MEGA16.COM with a hexa editor and replace the following bytes.

  • Replace "32 C8" by "F1 C9" at offset address 02121h
  • Replace "32" by "F1" at offset address 02132h
  • Replace "1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A" by "11 01 80 2A 06 00 ED 52 44 4D 05 62 6B 13 36 FF ED B0 2A 06 00 C3 03 01" at offset address 0255Ah.

Save and use this new MEGA16 command. This patch makes the -W option inoperative.