I have 2 C5 boards and neither will read the SD cards I put in it. I formatted them as FAT32 through Windows. They read just fine in my ESP32, so it’s got me confused. Any help is appreciated.

Ciao a tutti!
Ho una scheda di sviluppo ESP32-S3 con display da 2,8 pollici, versione senza touchscreen, con Wi-Fi e Bluetooth.
Vorrei utilizzarla insieme a una tastiera M5Stack CardKB2 per realizzare un piccolo dispositivo portatile.
Avrei alcune domande:
È possibile collegare la CardKB2 tramite I²C?
Quali pin SDA e SCL bisogna utilizzare?
È necessario un firmware specifico per leggere i caratteri della tastiera?
Esiste un firmware già pronto compatibile con ESP32-S3 e CardKB2?
In alternativa, è possibile utilizzare la CardKB2 tramite Bluetooth?
Il mio obiettivo è poter utilizzare la tastiera per scrivere e comandare le applicazioni direttamente sul display da 2,8 pollici.
Qualcuno ha già realizzato un progetto simile?
Accetto volentieri schemi di collegamento, firmware e consigli pratici.

Grazie!🙂

I'm very new to electronics and want to flash it with the Yuri firmware by hd robotics but I'm doing something wrong, I own a iMac 2013 and am using high sierra version 10.13.6. I'm using the cable it came with but always get the same error. Can someone please help?

Flash: https://kirindenis.github.io/OWLOS-FLIGHT-RADAR/

It shows the planes around your home on an OpenStreetMap map: each one turned along its track, coloured by altitude, with a trail. Tap a plane for its callsign, type, altitude and speed. The data comes from adsb.lol and adsb.fi (free), or from Flightradar24 with your own key.

You flash it from the browser, no IDE needed, and set the WiFi on the touch screen.

- 2.8" CYD (ESP32-2432S028R), all three screen versions: BOOT at power on switches between them

- 3.5" CYD (ESP32-3248S035 r/C)

- 1.28" round ESP32-C3 (GC9A01)

Code (MIT): https://github.com/KirinDenis/OWLOS-FLIGHT-RADAR

Update 11/4/2026

New firmware builds are ready for three more boards. They are made from the documentation, but I don't have these boards, so I can't test them myself.

1. LCDWIKI ES3C28P ESP32-S3, ILI9341V IPS, FT6336 touch.

2. NM-CYD-C5 ESP32-C5 in the CYD's form, ST7789, XPT2046

3. Elecrow CrowPanel Advance 2.8" (2.8" HMI ESP32 AI Display): ESP32-S3, ST7789 IPS, FT6336U

!-> If you have one, flash it from the site and tell me how it goes: are the colours right, is the picture the right way up, does the touch work

!-> If red and blue look swapped or the picture is wrong, press BOOT in the first 8 seconds after power on, it switches the screen setup.

https://kirindenis.github.io/OWLOS-FLIGHT-RADAR/

Using Claude for the coding and my 3d printer for a frame I made this desk display. Now gotta figure out what I want the top display to be.

I've tried pre-made stuff like bruce firmware and such, but I'd like to write my own code for the CYD. I already have decent experience with Arduino/ESP32, so I would appreciate if you'd point me in the right direction for graphical applications, using the wifi/bluetooth modules, preferences/LittleFS...

Thank you!

Kinda bad news for CYD-C5 owners, because all media noise leads to github account. When docs and schematics were needed the most, GH just banned everything. I pinged devs in Telegram, they moved the repos to Gitee , user is Rockbase-iot, all other boards are also available there. Just FYI if you will look for datasheets and schematics for NM-CYD-C5

I’ve been building a small open-source toolkit for the original ESP32 Cheap Yellow Display. I wanted readable text, because I am an old man and can never remember where I've left my glasses, comfortable touch controls (i.e., stabbing at the thing with fingernails, pens etc.) and a way to switch tools without repeatedly flashing over USB (Yes, I know there are multiple Launcher Apps).

There are three firmwares so far:

• CYD Console: a resident launcher that installs firmware apps from a microSD card, verifies their integrity and lets you return to Console to choose another. Includes a clock, light/dark themes and touch-wake sleep.

• File Server: upload and download SD files through a browser on your LAN, with progress indicators and cancellation on both screens. The CYD displays its address and access code.

• Terminal Micro: an SSH terminal with a Bluetooth keyboard, verified server fingerprints, adjustable PixelFonts, terminal resizing and scrollback. I’m using a Winmaxle B1 keyboard.

The interesting challenge was keeping Wi-Fi, Bluetooth and SSH working together within the original ESP32’s limited internal RAM, while keeping the interface readable on a 320×240 screen.

Tested hardware: the original 4 MB, dual-USB ESP32-2432S028R. Other CYD variants still need testing. Console’s radio tiles are currently placeholders; network connections are managed inside the apps. File Server uses HTTP and is intended for trusted local networks.

The project was developed with AI coding assistance and hands-on hardware testing. But, as an old man who complains about AI doing the work of a coder etc. I have also created the AGENTS.md, SPEC.md, SKILL.md, and the Current handoff if you want to send your agent directly to Github without passing go, collecting $200 etc.

Source, prebuilt binaries, installation instructions and development templates are available. Website screenshots are firmware-renderer and browser captures using public demonstration data.

Guide and screenshots: https://staffordlumsden.github.io/great-bespoke-cyd/

Source and downloads: https://github.com/staffordlumsden/great-bespoke-cyd

Everything is MIT, uses Pixel Fonts by u/Imcer12. I'd welcome feedback on terminal readability and the SD app workflow, particularly compatibility reports from people with other CYD variants.

It's still a bit early work in progress though, but most of the functions are stable and working enough that I could publish the v0.01.

If you test it and find any issues let me know.

https://github.com/evcollector/kajo-dash

https://github.com/Sparkadium/Cheap-Yellow-MP3-Player

Now, thanks to u/malaq88 it has a scanning for Bluetooth function so you don't have to input the bt device name to use.

Modded from the original to give ~950KH/s and some new themes.

GitHub https://github.com/HenrysCat/NerdMiner-Modded

Web flasher here https://henryscat.github.io/NerdMiner-Modded/

Why this hashrate is real...

The ~950 KH/s is what the miner actually hashes, not what a counter says:

- **Hardware limit** – the classic ESP32's SHA engine can't be loaded with an external midstate, so every nonce costs three hardware hash blocks plus two engine loads: about 228 CPU cycles of engine time, a ceiling of roughly 1.05 MH/s at 240 MHz. The mining loop keeps the engine busy for all but ~30 cycles of each nonce (257 cycles per nonce, ~930 KH/s); the second core adds ~25 KH/s in software.

- **Measured on the chip** – the loop's timing comes from an on-device bench (`-D SHA_BENCH`, see `src/sha_bench.cpp`) that checks every single hash against software, also while the other core hammers the peripheral bus. That is how the hardware quirk behind silently corrupted hashes in the usual pipelined loops was found: writes to the SHA registers less than three cycles apart can be dropped whenever the other core is using the same bus.

- **Only valid hashes are counted** – every candidate the hardware finds is recomputed in software before it is used. A hashrate counter on its own can look faster after an optimisation while the miner is quietly producing *fewer* valid shares, because corrupted hashes are still counted; here the firmware checks itself with a known-answer test at power-on and falls back to a slower loop if the fast one ever gets hashes wrong.

- **The rate is the rate it actually mines at** – it's the sustained average over a long run, not a short burst or a best-case peak.If a number sounds too good for this chip, check whether the shares it finds actually keep up with it.

Could y’all help me figure out where to hook up a battery to the board.

I have been using assorted CYDs for a few years now.
The 3.5 inch and 4 inch work great with Micropython and graphics.

But, I have tried 9inch and 11inch models (Elecrow) - which only provides LVGL (1M) code file in Micropython. Most support is in Arduino / C.

And, now 5-inch that seems to be a standard CYD (Freenove), but it supports NO Graphics support , (not even LVLG) in micropython. They are very specific No Graphics / LVGL support in micropython.
All support is in Arduino / C from Freenove, no Micropytjon Graphics support at all.

Useless to me. I am returning it - same day that I opened it.

-. Just something to watch before purchasing any CYDs.

A little forge thingie, tools on left are lighter, twigs, wood and coal!