This repository contains support for ClojureScript on the ESP32 WROVER using Espruino.
Set up an ESP32 WROVER with partitions and expanded JSVar space (the pre-built files below are modeled per this gist).
Note that schematics and other artifacts for a customized ESP32 WROVER board are available in the esprit-board repository, but any ESP32 WROVER with 8 MiB of PSIRAM will work.
We are assuming that the device is connected on port /dev/cu.SLAB_USBtoUART.
esptool.py --port /dev/cu.SLAB_USBtoUART erase_flash
Download bootloader, partitions, and Espruino engine:
Then flash via
esptool.py --port /dev/cu.SLAB_USBtoUART --baud 2000000 write_flash 0x1000 bootloader.bin 0x8000 partitions_espruino.bin 0x10000 espruino_esp32.bin
deps.edn:
{:deps {org.clojure/clojurescript {:mvn/version "1.10.597"}
esprit {:mvn/version "0.4.0"}}}
Make a REPL, baking WiFi credentials into it (change MySSID and MyWiFiPassword):
clj -m cljs.main -co '{:closure-defines {esprit.repl/wifi-ssid "MySSID" esprit.repl/wifi-password "MyWiFiPassword"} :optimizations :simple :target :none :browser-repl false :process-shim false}' -c esprit.repl
Normally we'd just have the Espruino persist the WiFi info via its existing capability to do so, but this is currently not reliable with this particular modified build, while baking it in as illustrated above works every time.
Then make a ROM binary from the compiled ClojureScript using
clj -m esprit.make-rom
You can then flash this ROM to your ESP32 via
esptool.py --port /dev/cu.SLAB_USBtoUART --baud 2000000 write_flash 0x2C0000 out/main.bin
To establish a REPL into the ESP32, we need to first learn its IP address. We can do this by connecting to it via the USB serial port:
screen /dev/cu.SLAB_USBtoUART 115200
Hit return to get a prompt and press the reset button on the device. It can take about 15 seconds to load the ClojureScript runtime) and configure the device to your WiFi network:
Once the device is connected to WiFi, it will print a message like the following to the serial port like:
Ready for REPL Connections
Establish an Esprit REPL by executing
clj -m cljs.main -co '{:def-emits-var false}' -re esprit -ro '{:endpoint-address "10.0.0.1"}' -r
Copy this command, and then exit your terminal session (in screen this is done via Ctrl-a, k, y), and then issue the copied command to start the REPL.
To compile your own code for use on the ESP32, you can use :optimizations :advanced in your project and then make a ROM for it by executing the esprit.make-rom main.
If you want to instead have a ROM with your code where you can establish a REPL, instead use :optimizations :simple and somewhere in your source tree, require the esprit.repl namespace.