---
name: "dgen"
section: "1"
platform: "linux"
package: "dgen-sdl"
version: "1.33-6"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/dgen"
---

# dgen(1)

Sega Genesis/Mega Drive emulator

## NAME

**dgen** – Sega Genesis/Mega Drive emulator

## SYNOPSIS

**dgen** \[**-Pfhmv**\] \[**-R** *(J\|U\|E)*\] \[**-H** *HZ*\] \[**-D** *DEMONAME*\] \[**-d** *DEMONAME*\] \[**-n** *USEC*\] \[**-p** *CODE,CODE...*\] \[**-r** *RCFILE*\] \[**-X** *XFACT*\] \[**-Y** *YFACT*\] \[**-S** *FACT*\] \[**-g** *(0\|1)*\] \[**-G** *XxY*\] \[**-s** *SLOT*\] *\[romname* *\[...\]\]*

## DESCRIPTION

The ROM image in the file *romname* is executed, as emulated on a Sega Genesis or Mega Drive running in 60Hz NTSC mode (unless the **-P** option is specified, in which case 50Hz PAL mode is used). *romname* should be in raw binary or SMD format, and may be compressed with [gzip(1)](/gzip/1.md), [zip(1)](/zip/1.md), or [bzip2(1)](/bzip2/1.md).

When *romname* isn't specified, DGen starts without a ROM. It can be loaded later from the prompt. When more than a single *romname* is specified, they are executed sequentially.

The options are as follows:

- **-H** *HZ*

  Use a custom frame rate, can be used to accelerate or slow down emulation.

- **-P**

  Emulate 50Hz PAL mode (as used in European models of the Mega Drive).

- **-R** *(J\|U\|E)*

  Emulator region. Without this option, DGen uses the first region mentioned in the ROM header. It should be combined with **-P** for PAL mode. See below.

  - (none)

    Autodetect (NTSC, 60Hz)

  - **-P**

    Autodetect (PAL, 50Hz)

  - **-R** *J*

    Japan (NTSC, 60Hz)

  - **-R** *J* **-P**

    Japan (PAL, 50Hz)

  - **-R** *E*

    Europe (NTSC, 60Hz, music will certainly play too fast)

  - **-R** *E* **-P**

    Europe (PAL, 50Hz)

  - **-R** *U*

    America (NTSC, 60Hz)

  - **-R** *U* **-P**

    Same as **-R** *E* **-P**

- **-f**

  Run fullscreen, if possible.

- **-h**

  Show a brief synopsis of all options.

- **-m**

  MinGW only. This option prevents DGen from detaching from its control console.

- **-v**

  Show the version number, and exit.

- **-D** *DEMONAME*

  Play back a demo recorded with the **-d** option.

- **-d** *DEMONAME*

  Record a demo of the program running, which can be later replayed with the **-D** switch.

- **-n** *USEC*

  Sleep for a number of microseconds after every frame, to give time to other processes.

- **-p** *CODE,CODE...*

  Modify the ROM image in memory, using Game Genie or Hex style codes. Game Genie codes are of the form *ABCD-EFGH* and Hex codes are in the form *123456:ABCD*. To specify more than one code, separate them with commas (do *not* use spaces).

- **-r** *RCFILE*

  Parse another rc file after $HOME/.dgen/dgenrc. Values in the specified file override those in the preceding files.

- **-X** *XFACT*

  Scale the window XFACT times in the X direction. XFACT must be a positive integer.

- **-Y** *YFACT*

  Scale the window YFACT times in the Y direction. YFACT must be a positive integer.

- **-S** *FACT*

  Scale the window FACT times in both directions. FACT must be a positive integer.

- **-g** *(0\|1)*

  Enable/disable OpenGL (if compiled-in).

- **-G** *XxY*

  Desired window size (e.g. 640x480, 800x600, etc.)

- **-s** *SLOT*

  Load the saved state from the given slot at startup (0-9)

## INTERACTIVE PROMPT

A minimalist interactive prompt inspired from [vi(1)](/vi/1.md) can be used to perform various operations described below. It is triggered by pressing colon (:), the default key. Command-line editing, history and completion are supported.

### Commands

- {quit, exit, q}

  Quit, or load the next *romname* from command-line, if any.

- {load, open, plug, o} *filename*

  Load a given ROM *filename*.

- {unload, close, unplug}

  Unload the current ROM.

- config\_load *filename*

  Load configuration from file *filename*.

- config\_save *filename*

  Save current configuration to file *filename*.

- reset

  Genesis reset.

- {ctv\_push, ctv\_pop, ctv\_none}

  Manage the stack of Crap TV filters (if compiled-in).

- calibrate *number*

  Interactive calibration of the specified gamepad (1 or 2). If *number* isn't specified, default to 1.

- unbind *binding* *\[...\]*

  Remove specified bindings (variables prefixed with "bind\_"). See [dgenrc(5)](/dgenrc/5.md) for more information about them.

- vgmdump start *filename*

  - vgmdump stop

  Manages VGM dumping/logging. If the second argument is *start* VGM dumping will be started at the path specified by the third argument. If the second argument is *stop* VGM dumping will be stopped and the dump finalized.

### Variables

All configuration variables from [dgenrc(5)](/dgenrc/5.md) can be displayed and modified interactively, with immediate effect.

- {int\_name, bool\_name, key\_name, joy\_name, ...} {value}

  Affect *value* to variable *name*.

- {int\_name, bool\_name, key\_name, joy\_name, ...}

  Display current value for variable *name*.

## FILES

- *$HOME/.dgen/dgenrc*

  Contains user settings for the emulator.

- *$HOME/.dgen/dgenrc.auto*

  Generated file containing saved user settings.

- *$HOME/.dgen/saves/\**

  Save states generated by the emulator.

- *$HOME/.dgen/ram/\**

  Battery-backup RAM images, generated by the emulator for ROMs with save RAM.

- *$HOME/.dgen/screenshots/\**

  Screenshots are generated there.

- *$HOME/.dgen/roms/\**

  ROMs default search path.

- *$HOME/.dgen/demos/\**

  Demos default search path.

## SEE ALSO

[gzip(1)](/gzip/1.md), [bzip2(1)](/bzip2/1.md), [zip(1)](/zip/1.md), [dgenrc(5)](/dgenrc/5.md)

## AUTHORS

This manual page was written by Joe Groff ⟨joe@pknet.com⟩. Updated by zamaz ⟨zamaz@users.sourceforge.net⟩.

## BUGS

There are known emulation bugs, see BUGS in DGen source package.

Report bugs to ⟨http://sourceforge.net/projects/dgen/⟩.