Every microcontroller project that logs data, schedules actions or shows a clock eventually needs to know the time. Getting it right is surprisingly hard: internal clocks drift, RTC modules need to be set, and NTP needs internet access, which you often don’t have in the field, in a workshop or on a battery-powered sensor. Yet the answer is probably in your pocket. A smartphone knows the time very precisely, from the network and from its Read more
“Time is what keeps everything from happening at once.” — Ray Cummings Every microcontroller has a heartbeat. A quartz crystal vibrates millions of times per second, a counter ticks upward, and the board always knows how long it has been since it woke up. But ask a freshly powered ESP32 what time it is, and it has no idea. It knows duration, not moment. It can count, but it can’t tell you whether it’s Tuesday Read more
If you want to run a TensorFlow Lite model on an Arduino today, you quickly find that there is no obvious answer. There used to be one: Google’s official Arduino package, Arduino_TensorFlowLite, built from tflite-micro-arduino-examples. That package has not been updated for a long time, and I think it is worth looking at how we got here and what you can use in the meantime. What happened to the official package The official package was Read more
Remember the screeching of the dial-up modem? Turning data into sound is still one of the simplest ways to connect devices: you can use an audio cable, send it from a speaker to a microphone, put it on a telephone line or a radio, or just store it in a WAV file. No Wi-Fi, no pairing, no extra hardware. TinyModem is a header-only C++ library of software audio modems for Arduino and the desktop. It Read more
If you look for speech recognition examples for microcontrollers, you almost always end up with wake word detection or keyword spotting: the micro_speech example of TensorFlow Lite Micro, which recognizes “yes” and “no”; Espressif’s ESP-SR with WakeNet for the wake word and MultiNet for a list of commands; keyword spotting models trained with Edge Impulse; or Picovoice’s Porcupine and Rhino. They work well for what they do, but they all classify a small, fixed set Read more
If you have ever streamed video from an ESP32, you have most likely used the CameraWebServer example: the camera delivers JPEG images, which the web server pushes one after the other to the browser. This works, but there is no sound, the bandwidth is high, and the result is not a real video stream that you could record or play in VLC. A real stream needs a video codec such as H.264, an audio codec Read more
Classic embedded text-to-speech (formant synthesizers like SAM or eSpeak) is tiny and fast, but it sounds like a robot from the 80s. Neural TTS sounds natural, but it is usually something you run on a PC or in the cloud. I wanted to know: what is the cheapest hardware that can run a neural text-to-speech model locally, faster than real time? To find out I ported tiny-tts to C++ as TinyTTS. It is a VITS-style, Read more
Why a tiny FPGA? I spend most of my time making microcontrollers do audio, graphics and machine learning, and I keep hitting the same wall: the CPU is too slow for the heavy inner loop. So I bought a cheap Sipeed Tang Nano 20K to see how far a hobby FPGA can push past that wall. Four projects later, the answer is: surprisingly far. The board is about the size of a stick of gum Read more
To produce the most natural-sounding speech, modern Text-To-Speach (TTS) systems rely on neural networks. TinyTTS is a proof of concept: It asks whether a VITS-style neural TTS model can run on a microcontroller at all. It is a header-only C++ port of tiny-tts. The model has about 1.6M parameters. It has four stages: text encoder, flow, duration predictor and a HiFi-GAN-style vocoder. There is no inference runtime such as TFLite Micro. Everything is hand-written C++ Read more
A follow-up to AudioTools video support, which covers container/codec selection (AVI vs. MP4 vs. MPG, MJPEG vs. H.264). This post is the other half: the pipeline that actually plays a file, a minimal sketch, and every class involved. Why this exists On a desktop, “play this video” hands the problem to an OS: a media framework demuxes the container, decodes on a scheduler-managed thread, and a compositor times frames to the display’s refresh. An ESP32 Read more