Difference between revisions of "32MB RAM expansion"

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By replacing the Dreamcast's two 8MB SDRAM chips with larger SDRAM chips, modifying the pin arrangement, and [[BIOS modification|modifying the BIOS]], it is possible to install 32MB of RAM in the Dreamcast. Existing games and applications will very likely not be able to address the RAM, but applications built with a patched version of [[KallistiOS]] are able to address all 32MB.
 
By replacing the Dreamcast's two 8MB SDRAM chips with larger SDRAM chips, modifying the pin arrangement, and [[BIOS modification|modifying the BIOS]], it is possible to install 32MB of RAM in the Dreamcast. Existing games and applications will very likely not be able to address the RAM, but applications built with a patched version of [[KallistiOS]] are able to address all 32MB.
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At the moment, the only known software able to take advantage of the 32MB RAM expansion is the [https://github.com/tsowell/scummvm-dreamcast/blob/dcalt-backend/backends/platform/dcalt/README.md Alternate ScummVM backend for Dreamcast] by tsowell. This version of [[ScummVM]] also offers an extensive array of other expansion hardware features, such as compatibility for loading/saving data with [[Serial SD card adapter|SD cards]] and [[IDE hard drive modification|hard drives]], the ability to output MIDI over [[MIDI adapter|serial]] or [[MIDI expansion|the expansion slot]] for external synthesizers, and the ability to output various VGA modes for CRT monitors.
  
 
A DreamShell image with 32MB patched BIOS images is available. This image contains a variety of nearly 50 BIOS images including the stock BIOS, japanese-cake BIOS, DreamBoot BIOS, and DreamShell BIOS, in a variety of flavors for each. This image also contains an updated bflash.klf module to support flashing the MX29L3211 32 megabit chips to accommodate triple-BIOS mods!  
 
A DreamShell image with 32MB patched BIOS images is available. This image contains a variety of nearly 50 BIOS images including the stock BIOS, japanese-cake BIOS, DreamBoot BIOS, and DreamShell BIOS, in a variety of flavors for each. This image also contains an updated bflash.klf module to support flashing the MX29L3211 32 megabit chips to accommodate triple-BIOS mods!  

Revision as of 19:45, 22 June 2020

By replacing the Dreamcast's two 8MB SDRAM chips with larger SDRAM chips, modifying the pin arrangement, and modifying the BIOS, it is possible to install 32MB of RAM in the Dreamcast. Existing games and applications will very likely not be able to address the RAM, but applications built with a patched version of KallistiOS are able to address all 32MB.

At the moment, the only known software able to take advantage of the 32MB RAM expansion is the Alternate ScummVM backend for Dreamcast by tsowell. This version of ScummVM also offers an extensive array of other expansion hardware features, such as compatibility for loading/saving data with SD cards and hard drives, the ability to output MIDI over serial or the expansion slot for external synthesizers, and the ability to output various VGA modes for CRT monitors.

A DreamShell image with 32MB patched BIOS images is available. This image contains a variety of nearly 50 BIOS images including the stock BIOS, japanese-cake BIOS, DreamBoot BIOS, and DreamShell BIOS, in a variety of flavors for each. This image also contains an updated bflash.klf module to support flashing the MX29L3211 32 megabit chips to accommodate triple-BIOS mods!

  • *WARNING* THE IMAGES ON THIS DISC ARE EXPERIMENTAL. THE ONLY TESTED 32MB BIOS IS THE jc-v1.032-32MB.bin IMAGE.
    • IF YOU FLASH YOUR DC BIOS WITH A 32MB BIOS IMAGE FROM THIS DISC, MAKE SURE YOU HAVE A FUNCTIONING BACKUP BIOS TO RECOVER YOUR DREAMCAST.
      • Seriously! We are not responsible for damage to Dreamcast units due to the use of this disc. Read the warning and know what you are doing.

See tsowell's blog for more information on the modification for now.