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MEGA Everdrive PRO Firmware (OS)

[   ] MEGAOS-V4.00.zip 2020-06-28 02:44

[   ] MEGAOS-V4.01.zip 2020-07-10 02:13

[   ] MEGAOS-V4.02.zip 2020-07-25 01:28

[   ] MEGAOS-V4.03.zip 2020-08-04 17:56

[   ] MEGAOS-V4.04.zip 2020-08-08 04:09

[   ] MEGAOS-V4.05.zip 2020-09-19 20:37

[   ] MEGAOS-V4.06.zip 2020-09-30 23:36

[   ] MEGAOS-V4.07.zip 2020-10-21 04:48

[   ] MEGAOS-V4.08.zip 2020-11-20 00:39

[   ] MEGAOS-V4.09.zip 2021-01-25 00:19

[   ] MEGAOS-V4.10.zip 2021-02-04 00:02

[   ] MEGAOS-V4.11.zip 2021-02-10 19:33

[   ] MEGAOS-V4.12.zip 2021-07-05 22:30

[   ] MEGAOS-V4.13.zip 2021-10-01 16:06

[   ] MEGAOS-V4.14.zip 2021-11-29 17:14

[   ] MEGAOS-V4.15.zip 2022-06-24 19:13

[   ] MEGAOS-V4.16.zip 2022-06-29 15:56

[   ] MEGAOS-V4.17.zip 2022-07-18 15:02

[   ] MEGAOS-V4.18.zip 2022-11-25 16:27

[   ] MEGAOS-V4.19-beta1.zip 2022-11-26 15:56


[   ] MEGAOS-V4.20.zip 2024-02-27 01:32

mega-ed-pro-manual.pdf 2022-06-29 15:45 971K

!!!We recommend backup your MEGA folder before than copy OS update!!!

MEGAOS-V4.20 27.02.2024
1) New cheats menu with text description for each code
2) Fixed SMS FM sound glitches (was already included in MEGAOS-V4.19-beta1)
3) Game Data menu. Jumps right to the saves/config folder of selected rom
4) Rom Configuration menu. Can change saves type and ROM region
5) Return from the system folder to the previous point instead of root dir
6) EFU installer support*
7) EEPROM save type assigned for "Turma da Monica na Terra dos Monstros"
8) If folder with cd-image contains bios.bin file, it will be loaded instead of regular bios
9) If the sms ROM folder contains the smsbios.sms file, then this ROM will be loaded along with this BIOS
10) Now can run cd-bios just like any other rom and enjoy the bios intro (yah, completely useless thing)
11) Minor changes in save states. Controller sniffer improvements

*Future OS versions will be distributed as single-file efu update.
Efu update can be installed right of the cart menu.

MEGAOS-V4.18 25.11.2022
1) Fixed SMS FM sound glitches
2) Save Staes update. Restore functions*
3) System folder hidden in file browser. Access to the folder via main menu

*In-game menu has two new items: "Restore Last Save" and "Restore Last Load"
"Restore Last Save" loads backup copy of save data overridden by the last "Save State" execution
"Restore Last Load" jumps to the point prior last "Load State" execution
System has two special save slots hidden from user
slot 99 stores backup copy of data overridden by last "Save State"
slot 98 stores the point where the last "Load State" was executed
"Save State" mechanism: system copies selected save slot to the slot 99, then write current state to selected slot
"Load State" mechanism: system copies current state to the slot 98, then load state from selected slot
"Restore Last Save" mechanism: load state from slot 99
"Restore Last Load" mechanism: load state from slot 98


MEGAOS-V4.17 18.07.2022
1) Fixed compatibility with early msu-md hacks


MEGAOS-V4.16 29.06.2022
1) MD+ fix
2) Fix for Super Bubble Bobble


MEGAOS-V4.15 24.06.2022
1) Changes in folders sturcture*
2) NES core update
3) Fixed compatibility for pairs of 32X+VA4 motherboards
4) Improved recently played menu
5) Minor fixed for Mega-CD
6) Seems like MD+ games works now, not sure how it happens
7) SMS audio update
8) Menu dialog for deleting empty folders

*Each game has own subfolder where stored all data related to it (saves, cheats etc.)
All game data located in MEGA/gamedata


MEGAOS-V4.14 29.11.2021
1) Fixed cd-audio activation for Pier Solar. Game wasn't detect cd hardware on some systems
2) Fixed glitches when used ram-cart function on Mega-SG
3) State recovery function*
4) Menu navigation works from both controllers
5) Changes in structure of save-state folder**

*99th save slots turn into recovery slot.
Before than new save data will be written to the any of save slots, old save data from current slot will be copied to the recovery slot automatically.

**Changes was made to prevent save/load state slowdown due the storing a large amount of files in save-state folder.
Now each game has own subfolder with save slots files inside.


MEGAOS-V4.13 01.10.2021
1) Fixed PCM buffer size for CD+cart configuration


MEGAOS-V4.12 05.07.2021
1) Data initialization for blank 24C08 eeprom
2) Included support for Demons Of Asteborg
3) CD hardware enabling if the "C" letter is found in the device support list (ROM address 0x000190)
4) In-game menu remember the last selected item


MEGAOS-V4.11 10.02.2021
1) Fixed Virtua Racing crash in Free Run mode when used in pair with Mega-SG
2) Fixed save type detection for Wonder Boy V - Monster World III (Japan, Korea)
3) Fixed save type detection for Rockman - Mega World (Japan) (Alt 1)
4) MSU-MD driver can switch-off seek time emulation


MEGAOS-V4.10 04.02.2021
1) Improved sd card handling in CD mode


MEGAOS-V4.09 25.01.2021
1) Fixed hang at "bram check" screen in Burai
2) Fixed crash after bios loading in Thunder Storm FX
3) Improved sd card handling in CD mode
4) Rom region selection option
5) Included Realtec mapper
6) Fixed HardBall '95
7) Fixed game loading over USB
8) Fixed region detection for some games
9) Included SF-004 mapper
10) Included SF-002 mapper
11) Included SF-001 mapper
12) Fixed Sonic Megamix

!!WARNING!! After this update cart will no longer be supported with older OS versions.
However, repair tool can be used for roll back to the older OS versions: http://krikzz.com/pub/support/mega-everdrive/pro-series/repair.zip


MEGAOS-V4.08 20.11.2020
1) Changed user mappers linking rules*
2) Another improvement for .cue parser
3) Built-in megacolor player. Change yours megacolor videos extension to .mcv to play them right from cartridge menu.
4) Association of certain file types with external applications function**

*Specific rom header isn't need anymore, just put mapper.rbf in game folder and game will be executed along with attached mapper (for developers)

**Since version 4.08 OS supports association of certain file types with external applications.
This feature mostly designed for external emulators, but can be used for other purposses also, for built-in megacolor player for example.
If file extension matches to one of folders name in MEGA/edapp then such file will be executed using app.md rom stored in this folder.
app.md will be loaded to begin of ROM memory space and target file will be loaded right after app.md.
System also can pass to app.md patch to the target file instead of including file data itself, it depends of config.txt stored in app.md folder.
Also app.md can use own custom maper if mapper.rbf stored in same folder along with app.md
Refer to MEGA/edapp folders details

***Early megacolor-player not longer supported, player update required


MEGAOS-V4.07 21.10.2020
1) Cartridge UI customization support support*
2) "Last Game Autoboot" option. Runs last played game automatically at cold start. Hold C during system boot to return in menu
3) .cue parser improvements
4) Minor optimizations for system functions acceleration, faster return from game to menu, etc.

*Menu themes supports static images, fullscreen scrolling, per tile scroling, menu colors modifications.
Themes can be installed using cartridge menu, just hit at .bgr file and click "Set Theme"
Look megatheme tool for details: http://krikzz.com/pub/support/mega-everdrive/pro-series/megatheme/


MEGAOS-V4.06 30.09.2020
1) Fix for Pier Solar when playing with cd-audio (was accidentally broken in v4.05)


MEGAOS-V4.05 19.09.2020
1) Fixed audio clicks when using cd images with wav tracks
2) Fixed problem when save-state preview via in-game menu causes state loading
3) Fixed controllers lock-up in j-cart tennis games
4) SRAM switched off for Puggsy
5) Fixed audio drops during Popful Mail FMV
6) Minor system improvements


MEGAOS-V4.04 08.08.2020
1) Saves management changes.*
2) Fixed volume register overflow in PCM low pass filter
3) Fixed Snatcher crash after "corpse reconstruct" cut scene
4) Fixed audio track cutting for bin+wav cd images
5) Mapper for Sonic Delta

*System will move save data from battery ram to SD card every time when cartridge boots to menu (instead of moving when game changed).
It makes save system more clear and prevent lost of data for last played game if battery dry out.


MEGAOS-V4.03 04.08.2020
1) Fix for games which using "reset" instruction


MEGAOS-V4.02 25.07.2020
1) Fixed pause for MegaSG in SMS games
2) Fixed SMS in-game menu for MegaSG
3) Support for CD images with data tracks in MODE1/2048 format
4) Included YM2413 core update from Necronomfive
5) RAM cheats (including Mega-CD)
6) OS can load custom user mappers from the ROM catalog without copying it to the system folder. rbf file name should match to the mapper number
7) Aside of system folder OS will seek IPS patches in ROM folder also (patch name should match to the ROM name)
8) Speed improvement for IPS parcher
9) Included MSU-MD patch for ToeJam & Earl in Panic on Funkotron. Thanks to @32mbit for making this patch. http://tinyurl.com/msu-md
10) Minor system improvements


MEGAOS-V4.01 10.07.2020
1) Fixed problem with SMS FM sound when it stops working if smsbios.sms not exists
2) Multi-bin CD images support*
3) Save states preview right from In-Game menu (genesis mode only)
4) Ips auto patcher**
5) Included msu-md ips patches for games which been previously hacked for MD+***
6) Region fixes related to MegaSG

*CD images storing rules changed. Please reffer to online manual for details: http://krikzz.com/pub/support/mega-everdrive/pro-series/mega-ed-pro-manual.pdf

**Built-in auto patcher engine allow to use ips patches without using patching software. Rom stays unchanged on disk but patched in cart RAM.
ips-msu folder for games executed in pair with CD (ROM+CD), ips-std for all other games.
There two ways for path and ROM association:
1. Patch name should match to ROM ID. ROM ID can be obtained in "Rom Info" menu.
2. Patch and ROM name should be the same.

***Just put original unpatched rom and CD image to the same folder, cue file name should match to the rom name. MD+ audio pack can be used as is for msu-md.
msu-md patches also can be used with any other flashcart in pair with original Mega-CD, in this case rom should be patched manually and audio packs should be burned to the disk.