The ESP32-P4 is the new hotness on the microcontroller market. With RISC-V architecture and two cores running 400 MHz, to ears of a certain vintage it sounds more like the heart of a Unix workstation than a traditional MCU. Time’s a funny thing like that. [DynaMight] was looking for an excuse to play with this powerful new system on a chip, so put together what he calls the GB300-P4: a commercial handheld game console with an Expressif brain transplant.

Older ESP32 chips weren’t quite up to 16-bit emulation, but that hadn’t stopped people trying; the RetroGo project by [ducalex] already has an SNES and Genesis/Mega Drive emulation mode, along with all the 8-bit you could ask for. But the higher-tech consoles can run a bit slow in emulation on other ESP32 chips. [DynaMight] wanted to see if the P4 performed better, and to no ones surprise, it did.

If the build quality on this handheld looks suspiciously professional, that’s because it is: [DynaMight] started with a GB300, a commercial emulator platform. Since the ESP32-P4 is replacing a MIPS chip clocked at 914 MHz in the original — which sounds even more like the heart of a Unix workstation, come to think of it — the machine probably doesn’t have better performance than it did from factory unless its code was terribly un-optimized. In this case, performance was not the point. The point was to have a handheld running RetroGo on this specific chip, which the project has evidently accomplished with flying colours. If you’ve got a GB300 you’d rather put an “Expressif Inside” sticker on, the project is on github. Otherwise you can check out the demo video below. (DOOM starts at 1:29, because of course it runs DOOM.)

The last P4 project we featured was a Quadra emulator; we expect to see a lot of projects with this chip in the new year, and they’re not all going to be retrocomputer-related, we’re sure. If you’re cooking up something using the new ESP32, or know someone who is, you know what to do.

Emulating older computers on microcontrollers has been a staple of retrocomputing for many years now, with most 8-bit and some 16-bit machines available on Atmel, ARM, or ESP32 platforms. But there’s always been a horsepower limit, a point beyond which a microcontroller is no longer enough, and a “proper” computer is needed. One of those barriers now appears to have been broken, as microcontroller-based emulation moves into the 32-bit era. [Amcchord] has the Basilisk II emulator ported to the ESP32-P4 platform, providing a 68040 Mac able to run OS8.1. This early-1990s-spec machine might not seem like much in 2026, but it represents a major step forward.

The hardware it uses is the M5Stack Tab5, and it provides an emulated Mac with up to 16 MB of memory. Remember, in 1992 this would have been a high-spec machine. It manages a 15 frames per second refresh rate, which is adequate for productivity applications. The emulator uses the Tab5’s touchscreen to emulate the Mac mouse alongside support for USB input devices. To 1990 hackers, it’s almost the Mac tablet you didn’t know you would want in the future.

We like this project, both because it’s advancing the art of emulation on microcontrollers, and also because it delivers a computer that’s useful for some of the things you might have done with a Mac in 1992 and could even do today. Pulling this out on the train back then would have blown people’s minds. There’s even a chance that MacOS on something like this would turn a few heads in 2026. It’s certainly not the first emulated Mac we’ve seen though.