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Comment by intpx | Hacker News Reader

am I wrong or is the code the interesting thing here-- and not specific to this devboard? Is there anything special about this board other than it 1. looks nice 2. supports the project 3. has the requisite 8+ Mib of PSRAm 4. has a silkscreen bug? genuinely asking as I am really still trying to figure out what i don't know about microcontrollers and embedded devices

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I was also curious, and from their Design repository:

> Note: You don't need to use this particilar board to run ClojureScript.

> Any ESP32 WROVER with 8 MiB SPIRAM is capable of running a ClojureScript REPL

https://github.com/mfikes/esprit-board/#esprit-board

I also looked at the schematics, which is your standard ESP devboard layout.

Edit: I'm not an expert, but have used tons of ESP based dev boards so there are a couple very frequent issues I've observed. Usually I have had trouble if the USB-UART chip is not wired correctly or doesn't reset quick enough. Lower baud rate makes it work. Also, the GPIO numbers on silk screen may not be correct, so double check those.

Indeed, the board is not required. I've added a note to the Tindie description to that effect.

I created the board for an upcoming Clojure/north 2020 talk https://clojurenorth.com/mike-fikes.html

But, your assessment is correct... the software is definitely the interesting bit (the challenges associated with getting ClojureScript to run on that hardware, with a REPL, etc.)

It seems to require anything that can run the "Espruino" base, so this link probably covers that: https://www.espruino.com/Other+Boards

The primary challenge is RAM. The (simplistic) approach I took with establishing a ClojureScript REPL is to have the standard library available, and that requires a lot more RAM than most Espruino boards have. Even with the ESP32, I had to make a few tweaks to Espruino in order to make more of the ESP32's RAM available.

Perhaps a more sophisticated approach could be devised involving "faulting in" ClojureScript standard library functions on demand as they are used, and by doing this use less RAM and reduce startup latency. If that were done, things would run on a broader range of chips (less RAM needed).

I bet a port to the Teensy 4 would be popular for some use cases. No wifi, but 600Mhz, gobs of RAM, and ~$20.

I thought it only had 1MB of RAM?

Might be an interesting target for Janet though!

Argh, you're right. I hadn't picked up that the WROVER boards have even more RAM.

Normally 1MB is "gobs" in the microcontroller world. The ~8MB in the WROVERs is a crazy amount of RAM for an mcu.

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