Esp32sim
Dev tools
microcontroller emulator
SHOW HN2026
How HN took it
11 positive, 11 neutral or asking, 0 mixed, 5 critical, out of 27 comments about the project. Thread score +0.23.
Idea: 3 for, 1 againstDocs: 0 for, 3 againstPricing: 1 for, 0 against
The thread, comment by comment
Each row is a top-level comment and its replies, in HN's order. Select a cell to open that comment on HN.
positive neutral or mixed critical about another commenter or something else the maker
What HN said
What people liked
Useful for testing firmware without hardware, including CI.
From 2 comments
Outstanding! Very cool. On a lot of IoT projects, it's easier to create a "functional" software simulator for the hardware part so the mobile and cloud people can get going…
raminf on HNYes, it is also very very useful when doing agentic coding of ESP32 software - no messing with HW until you have something that works reasonably well already. So less time spent…
joakimeriksson on HN
Free and open source alternative to paid emulators.
From 2 comments
OSS and the price? It may be vibe coded but the price is free.
crazysim on HNI have tried to use wokwi several times and I ran into roadblocks trying to do what I want with it. They want you to pay and that’s limiting. I get trying to extract value for…
matthewfcarlson on HN
Objections
README is too long and poorly formatted, AI-generated looking.
From 2 comments
I actually want to have a play with this sometime. But honestly, these gigantic, poorly-formatted AI-slop paragraphs like the one below this heading……
dofm on HNI can tell that a README.md becomes a DONTREADME.md when its contents are: ``` 1) As long as a novel. 2) Poorly formatted. 3) Has several claudisms in each sentence. ``` It is…
rvz on HN
Emulation fidelity of peripherals may not be enough to replace hardware.
From 2 comments
The challenge is is getting the peripherals emulation detailed enough to be useful - and in reality it'll never be good enough to completely replace physical hardware because…
crote on HNOnly if the emulator emulates the timings faithfully; Also it probably needs to emulate the dma/rmt subsystem at a timing level. Vaguely related, I recently designed a ws28x…
aforwardslash on HN
Requests
Support for ESP32-P4 and H2 chips.
From 2 comments
Very nice! Are you planning P4 support? Have lots of S3 units and some C6, but P4 are the ones getting the most attentation at the moment.
snakeman on HNAny plans to support H2? This is awesome, I will certainly use it for some of my recent embedded work. Will try and contribute back as well.
noah_buddy on HN
ESP-NOW and mesh support.
From 1 comment
It supports espnow and mesh features?
eduardsik on HN
RP2350 support.
From 1 comment
Is there one for RP2350?
djmips on HN
Questions
How does it differ from Wokwi?
From 1 comment
How is this different from Wokwi.com? They’ve been doing for years, and have a large number of microcontrollers emulated.
turbine401 on HN
Alternatives named
Wokwi
From 1 comment
How is this different from Wokwi.com? They’ve been doing for years, and have a large number of microcontrollers emulated.
turbine401 on HN
Velxio
From 1 comment
A fantastic project. I've used velxio.dev it also runs in a browser with ESP32 and other microcontroller emulation, circuit simulation, and AI-assisted development
noahnathan25 on HN
Espressif esp-emulator
From 1 comment
It seems Espressif is also on working something similar here: https://github.com/espressif/esp-emulator But source code is not yet available :-( Would be interesting to compare…
0xmaxallen on HN