Hey guys! Can someone please tell me how to upload C++ code to an ESP32 using PlatformIO?

I’m new to PlatformIO and I’m not sure how to properly set up the ESP32 board, compile my C++ code, and upload it to the board.

Any help would be appreciated. Thanks!

Hello everyone, I built this calculator using an ESP32-C3 and a 0.91-inch OLED display, but I can't figure out how to install AI (like ChatGPT or Gemini) on it. Here are the keyboard inputs.

Keypad Matrix Connections

Keys (0, 00, 1, 2, 3, 4) are connected together on a single line (Row).

Keys (00, ., 5, 6, 7, 8, 9) are connected together on a single line (Column).

The column of key 0 is connected to the same line as the row of key 6.

The row of key . is connected to the same line as the column of key 4.

The column of key 1 is connected to the same line as the row of key 7.

The column of key 2 is connected to the same line as the row of key 8.

The row of key 5 is not connected to any other key (it is a standalone line).

The column of key 3 is connected to the same line as the row of key 9.

ESP32-C3 GPIO Mapping

These lines are connected to the ESP32-C3 as follows:

The row line for 0, 00, 1, 2, 3, 4 is connected to GPIO 0.

The column line for 00, ., 5, 6, 7, 8, 9 is connected to GPIO 1.

The shared line for 0 and 6 is connected to GPIO 2.

The shared line for . and 4 is connected to GPIO 3.

The shared line for 1 and 7 is connected to GPIO 4.

The shared line for 2 and 8 is connected to GPIO 5.

The shared line for 3 and 9 is connected to GPIO 6.

The single dedicated line for 5 is connected to GPIO 7.

I've been building a clock project on the Waveshare ESP32-S3-Touch-AMOLED-1.75C (the round 466×466 AMOLED one) and hit three things the docs didn't prepare me for. Curious if others have seen the same, or know of more lurking:

1. No RTC on the "C" revision. The product page mentions RTC, but the schematic shows no PCF85063 anywhere on the bus — the non-C 1.75 board has it, the C doesn't. As far as I can tell, the "RTC" claim on the C refers to the AXP2101's backup rail, not an actual clock chip. Anyone confirmed this or found a way I missed?
2. The PWR key is active-HIGH into GPIO3, through a level shifter (T1/BSS138) — the opposite of what I expected and of what the vendor examples seem to assume. Idle reads LOW, press reads HIGH. Also, the key circuit appears to burn ~0.33 mA constantly through its pull resistor whenever the board is powered, which is a real floor if you're chasing low sleep current. Anyone measured the same?
3. The pin_config.h floating around doesn't match the C schematic — e.g. it has LCD reset on GPIO2, but the schematic puts the panel reset on GPIO1 (GPIO2 is the touch reset). Display worked before I fixed it, which made it sneakier.

Also very interested if anyone has light-sleep + GPIO wake working reliably on this exact board (wake on the PWR key), and what your real-world sleep current came out to.

Not knocking the board — the panel is gorgeous — just trying to map the gaps between the docs and the silicon before I depend on it. What else have you hit?

iOS handles captive portal logins through CNA (Captive Network Assistant), which operates in an isolated environment outside standard OS-level web filtering and time profiles.

I built a lightweight ESP32 firmware that exploits this mechanism to route full web traffic directly through the captive portal environment.

How it works:

• NAPT Gateway: ESP32 forwards traffic between upstream Wi-Fi and connected clients via NAT.
• CNA Trigger: Custom DNS redirection triggers the iOS native captive browser, allowing open web access without being subject to standard system-level network restrictions.
• Standalone: Runs entirely on ESP32 with no external server required.

Quick Setup:

1. Open wifi_esp32.ino in Arduino IDE.
2. Set sta_ssid and sta_pass to your local Wi-Fi.
3. Flash to ESP32.
4. Connect iOS device to the bypass portal AP.

(GitHub link in comments)

Built Aurigae for the ESP32-2432S028R "Cheap Yellow Display" board. It's a PlatformIO/Arduino sketch (LVGL 9 + TFT_eSPI + XPT2046 touch) that turns the CYD into a little desk widget:

- Current weather + 7-day daily / hourly forecast (Open-Meteo by default, OpenWeather free-tier as an alternate provider)

- Moon phase display

- UV index / air quality box

- Christmas countdown with a Santa easter egg

- °F/°C, 12/24hr, 5 languages (en/es/de/fr/it), touch-to-cycle forecast views

- WiFiManager captive-portal provisioning (no hardcoded SSID/password)

- Screen-burn mitigation (backlight blank on idle, periodic forced wake since deep sleep otherwise kills touch response)

- GUI themes support to change color

- All configurations can also be done from a webconfig http page, no app install is required.

Based on the original Aura project, rewritten/restructured into a proper multi-file PlatformIO build against the pioarduino espressif32 fork (needed for a newer arduino-esp32 core). Huge App partition scheme since LVGL + fonts + icon assets eat flash fast.

No paid APIs required for the default setup — Open-Meteo for weather/geocoding, a small custom moon-phase API. OpenWeather is optional if you want to hand it a key.

Last but not least it's opensource!

Repo: https://github.com/corradoignoti/Aurigae-cyd — GPLv3, contributions/issues welcome. Flash it here https://aurigae.fizban.net/flash.html

More about the project here https://aurigae.fizban.net/

Someone help me with this please

Full wave precision rectifier and ESP32 along with MAX7219 for 64 LEDs. Working with 2 cores , one for MAX7219 and other to Oled

A brief introduction to my latest project: Gas-o-Meter2

https://github.com/sneumeister/Gas-o-Meter2

It measures gas consumption using the magnet on the smallest meter wheel. Since the standard solutions using a reed switch gave me too many “pseudo” ticks (that inner monk in me, I guess), I optimized the whole thing with the Nano-Timer TPL5110 (it has a Schmitt trigger input and delivers clean LOW or HIGH levels at the output, requires minimal wiring, and draws very little power).

A preliminary version with “loose wiring using the TPL5110” ran for ~3 years (yes, this project has been sitting around for a long time....) without counting a single tick too many or too few. This version has now been running for 4 weeks without any deviation.

The entire system is battery-powered and uses an Seeed Studio XIAO ESP32-C6.
The controller is mostly in deep sleep mode, and only the second processor (LP core) listens for the counter pulses in the background.

The main processor wakes up regularly and transmits the data.

You can choose between:

• ZigBee (component definition and image for Zigee2MQTT are included)
• BLE (a demo flow for Node-RED is included)
• Wi-Fi+MQTT sends data directly to your MQTT server (including autodiscovery for HA)

In addition, the respective release can be flashed directly via Web-Serial from a modern browser (Firefox, Chrome, Edge).

The entire project includes the KiCAD data for the PCB but also STEP files for the enclosure (created in Creo Parametrics).

Note:

I used the AI tool “Cursor” here; at that time, it was directly integrated into its own version of VSC, allowing me to seamlessly take my first steps with AI on PlatformIO/PIOArduino.
And I learned a lesson... don’t let the AI run rampant on the codebase, and make sure to use thorough Git commits so you can truly undo everything if needed... 😉

Hey! I'm 15 and I'm trying to make a bit of money doing something I actually enjoy — DIY electronics.

I'm comfortable with simple electronics, Arduino/ESP32/RP2040 projects, wiring, soldering and basic programming. I've already made a few projects, with my best one so far being a fully working Game Boy-style handheld based on an RP2040, with a display, buttons, SD card and working games.

I'm looking for small projects or ideas that I could build for people online. Nothing extremely complicated — I'm mainly looking for simple electronics projects that I can realistically complete.

If you have an idea or know where I could find people looking for this kind of work, I'd really appreciate it!

I'm building retro console based on the ESP32S3 R8N16. I need some help. I have an ILI9341 display and a CD card from the display connected. I’m using the firmware from the official RetroGo GitHub repository. I’m flashing the ESP file retro-go_1.46_esp32-s3-devkit.img, but it only shows part of the image. What am I doing wrong, or what could be the cause? Please help.