From GameBrew

Last Updated2006/08/26

DGen PSP is an emulator of the video game home console Sega Megadrive/Genesis, which is based on the open source emulator DGEN/SDL v1.23.


Make a folder DGEN and place the unzipped contents in the folder.

Create the following folders inside DGEN folder: ROM, STATE, SAVE, CHEAT, CFG.

Copy DGEN folder to the /PSP/GAME/ folder on your Memory Stick. Place rom files in the ROM folder.

User guide

Supported formats


Each compressed file can contain only one rom file. Also note that not all proper TGZ checks are in place.

Menu Screen

It comprises of 5 different sections for State Save, Cheats, Settings, Key Config and System.

Below are some of the recommended configurations/settings that would be suitable for most games.

  • PSP CPU Freq - Default at 333MHz (recommended).
  • CPU Core Emulation - Might improve performace slightly for some games.
  • BGM Speed ​​Fix - Fix the background music to a specific speed.
  • Auto SRAM save - Stores game data in the PSP ram.
  • Country priority - For games that need a specific region to run (only use if the rom does not load).
  • Fix Checksum - An internal check of the emulator.
  • Comm mode - Enable multiplayer mode. See last section of the tutorial.
  • Max FPS - Set limit to number of frames if any game is too fast.
  • Max Frame Skip - Recommend 1 or 2.
  • Skip type - Automatic, Fixed and Reverse Fixed (Fix+Frame Skip value).
  • Frame Skip on Turbo - Regulate the Frame Skip of the roms in Turbo mode.
  • Screen Mode - Change screen resolution in roms. Recommend full screen.
  • Show FPS - Show/hide frames per second.
  • Show Background Image - Show/hide background image.
  • vsync - Vertical sync. Makes the emulator work just the same speed as the MegaDrive. Sometimes it consumes resources in excess, you may turn off to improve performance.
  • Palette Mode - Normal, Brightness, Contrast, etc.
  • Sound Mode - Recommend 44100 KHz.
  • Sound Volume - Regulates the volume.

There are other sound parameters including YM2612 Enable, PSG Enable, DAC Enable and Turbo Mode, which does not seem to have much noticeable difference to the performace.

Cheat List

This is where you enter the cheat codes, and they will be saved to the CHEAT folder.

In the Cheat List menu, select No/the number cell to display the cheat code input screen. You can click the check box to enable cheat after entering the cheat code.

It supports address from 0 to FFFFFF or Game Genie Code (be careful if you enter the wrong address, it may freeze).

Ad-hoc Multiplayer mode

For multiplayer mode, it is recommedned to assign the same channel to the two PSP in the XMB beforehand.

On both consoles, load the same game and access the menu. Set Comm mode in the Config menu to 1P (adhoc) and 2P (adhoc).

Go back to the game and wait a few seconds for the PSP to synchronize. The emulation will begin automatically. Controls assigned to the players are as follows.

  • Player 1 - Server controls.
  • Player 2 - Client controls.

Use menu display key to disconnect.

It is advised that both consoles use the same Frame Skip settings. Some settings/functions will be synchronized (Game reset, Turbo mode and State load) and some (Cheats, CPU adjustments) will be invaild during multiplayer mode.

Notes from developer:

The default CPU speed is set at 333MHz, the standard warnings apply. The speed can be changed to the PSP standard of 222 in the Menu screen.

In case of a system freeze, please wait 10 ~ 20 seconds. Then turn off the power and turn on the system once more. If needed, try holding down the power switch for a longer period of time.

Don't turn off the PSP if the Memory Card Access Lamp is flashing.

There are no checks for free space on the Memory Card, so make sure you have space before playing (If there is no space on the Memory Card, the program will crash).


L - Access Menu (definable via config)

L/R - Switch menu screen pages


Circle - C

Cross - B

Triangle - B (Quickly)

Square - A

R+Circle - Z

R+Cross - Y (Quickly)

R+Triangle - Y

R+Square - X

Select - MODE

Start - Start

R+Select - Save game

R+Start - Load game

R+Analog Up - Screen Mode

R+Analog Down - Show FPS

R+Analog Left - Volume Down

R+Analog Right - Volume Up

Cheat List:

Circle - Display cheat code input screen

D-Pad Up/Down - Select numerical value

D-Pad Left/Right - Select digit





v1.70 2006/08/26

  • Approximately 20% faster.
  • Added "BGM Speed ​​Fix" in [CONFIG] (If turned on, the sound will not slow down even if the processing becomes heavy. However, depending on the game, there may be no effect or problems may occur. Default to OFF then using Adhoc).

v1.60 2006/06/06

  • Fixed some game bugs.
  • Fixed bugs in 6 button mode.
  • Fixed some other minor bugs.

v1.50 2006/05/13

  • Shadow / Hilight mode support.
  • Added 6-button mode ON/OFF to key config.
  • Added "Palette Mode" in [CONFIG].
  • Added "Fix Checksum" in [CONFIG].
  • Analog (up) + Cross on the menu screen for game reset.
  • Fixed many game bugs.

v1.40 2006/04/01

  • Added wireless communication battle function (Refer to adhoc.txt/adhoc_eng.txt for details).
  • The simple communication battle function has been deleted.
  • Fixed to adjust the speed when Frame Skip 0.
  • Fixed that turbo did not work when Frame Skip 0.
  • Fixed to return to the menu when sleeping and waking up during the game.
  • Added exit (return to PSP menu) from the menu screen ("Analog (left) + Start" in the menu screen).

v1.30 2006/01/20

  • Implemented turbo mode (added to key config).
  • Added state deletion function (Select + Square).
  • Added state save / load confirmation message option.
  • State save date display.

v1.20 2005/12/01

  • Core Switches.
  • Switched 68K core to high-speed MUSASHI 3.3.
  • Switched Z80 Core.
  • High-speed 68K Core and Z80 Core appropriated from NeoCDPSP (thanks Yoyofr).
  • Added key config for core switching/reset.

v1.11 2005/11/01

  • Fixed a bug introduced in v1.10 with SRAM not saving correctly.
  • Super Sexy Smiths' English Readme.

v1.10c 2005/10/31

  • Quasi-wireless play (See Readme).

v1.10 2005/10/23

  • No speed loss with VSYNC: ON.
  • Added frame skip type.
  • Added 4:3 Screen Mode Option.
  • Sound improvements (specifically DAC).

v1.00 2005/10/07

  • Fixed bugs from v0.93 -> v0.95.
  • Fixed a freeze bug when PSG was disabled.
  • Fixed a bunch of game compatibility problems.
  • Fixed a bug in strange sound after State Load.
  • Fixed bug in odd sound output after changing sound settings.
  • Sound improvements (specifically DAC).
  • Performance Improvements.

v0.95 2005/09/12

  • Cheat Code support.
  • Some changes to Skin format.
  • Added automatic sleep on low battery.
  • Fixed a bug in saving settings on power off.

v0.93 2005/09/04

  • Menu screen fixed (skin support, color config, etc.).
  • Battery temperature, time remaining added.
  • Added ability to use L/R buttons.
  • Speed improvements

v0.90 2005/08/19

  • SRAM support.
  • ZIP, GZIP support (.ZIP, .GZ, .TGZ extensions).
  • PNG support for images.
  • ROM folder selection.
  • Fixed a bug in file sorting.
  • Speed improvements.

v0.80 2005/08/02

  • State Saves.
  • Fixed a bunch of game compatibility problems.

v0.70 200507/18

  • Settings saving.
  • Key Config.
  • Screen mode selection (Fit, Full).
  • Sound volume settings added.
  • Fixed a bug in left/right sound output.

v0.60 2005/07/09

  • Sound improvements.
  • Sound settings (11/22/44KHz, DAC).
  • Region settings.
  • Speed improvements.
  • Key repeat in menu screen.

v0.50 2005/07/02

v0.10 2005/06/18


Special Thanks to Mirakichi, Bifuteki, Ruka, Smiths, Yoyofr, People who have submitted bugs/feedback, Naga10 Font creators, DGen/SDL authors and countless others.

External links