The Sega Dreamcast was a extremely quirky console and whereas it was underappreciated when it was accessible, with comparatively poor gross sales, it has garnered a considerable cult following since Sega discontinued the consoles in 2001. One among its most fascinating options was the Digital Reminiscence Unit (VMU), which was a reminiscence card packaged in a module with its personal tiny LCD and buttons. It had some fascinating capabilities, together with supporting some minigames all by itself, individually from the Dreamcast console. DynaMight dramatically expanded on that by making a VMU able to operating “actual” video games, together with Doom.
To allow its distinctive performance, Sega gave the VMU a CPU and RAM of its personal. However that was extraordinarily restricted—nearly any pocket calculator accessible in the present day could have extra energy. There is no such thing as a probability {that a} VMU might run something past the sorts of simplistic minigames it was designed for, which is why DynaMight needed to exchange all of that. They’re, basically, utilizing the VMU shell and buttons for contemporary {hardware} that has much more processing energy and RAM.
That {hardware} is an ESP32-WROVER-E N4R8 microcontroller. For a microcontroller, that’s fairly highly effective. It has an Xtensa dual-core 32-bit LX6 processor that may run at 240MHz and 520KB of SRAM, plus a further 8MB of PSRAM linked via quad SPI. DynaMight paired that with a full-color 1.69” IPS show and a tiny speaker. These parts go on a customized PCB with built-in button pads. Energy comes from a 600mAh lithium battery.
DynaMight designed the PCB to suit right into a VMU shell, nevertheless it isn’t a easy drop-in substitute. Some modification of the VMU shell is important to make room — principally trimming the interior ribs that present structural help. A easy 3D-printable spacer helps to help the show after making these modifications.
To run video games, DynaMight chosen Retro-Go. That’s firmware constructed for ESP32 microcontrollers to run emulators for a number of techniques, together with the NES, SNES, Recreation Boy, Recreation Boy Coloration, Sega Genesis, Sega Recreation Gear, Colecovision, and Atari Lynx. Retro-Go has a whole lot of optimization tips beneath the hood to assist run these emulators on the comparatively low-spec {hardware}.
And, better of all, Retro-Go helps Doom and which means DynaMight was capable of accomplish the normal feat of operating Doom on their machine. DynaMight says that truly taking part in video games on the VMU isn’t very comfy, as a result of its small dimension, however that is nonetheless a really cool challenge.
