The firmware is about 110K lines: MIDI recording + streaming, USB, Bluetooth, Wi-Fi, web APIs, storage, OTA updates, diagnostics, security, peripherals, provisioning, and an embedded web interface.
There’s a lot required to make a full-featured product.
Nearly every component gets tested: sdcard, clock, battery, anti-counterfeit IC, led, buzzer, the tactile-switch!
I suspect that 110k number might include the ESP-IDF libraries as well as his own code.
I've written a fairly feature-complete handheld device based on the esp32-s2 and the codebase is about 9k sloc of the C I've written, but that number explodes to almost 40k sloc if I include the esp-idf's imported libraries.
How did you find customers?
How did you get your hardware design verified?
1) Does device record ALL MIDI sent to it? (Including e.g. SYSEX and non-registered parameters?
2) I edit MIDI on a Desktop (NOT a phone). a) Are sessions recorded into separate files? Named and/or dated? b) Can I inspect & load sessions from the card?
But why do you spell MIDI in lowercase there?
> plugs into your piano via midi
The real answer: I got tired of deciding what should and shouldn't be capitalized. Sounds easy but it gets ambiguous fast.
I'll revisit this decision at some point. Capital letters do make reading easier.
Can you expand? What counterfeits do you see (literally someone selling boxes labelled jamcorder? How do you handle that? Lots of scanning amazon and sending cease desist letter?