Ravi ReddyandClaude Opus 5.5
3b371cdb28
VoiceNotes is an Arduino sketch for the Waveshare ESP32-C6-LCD-0.85 that records meetings and voice memos to microSD and turns them into notes: - Records 16 kHz mono WAV (up to 4 h) from the ES7210 dual mics, with a boosted preamp and soft-limited digital gain - Transcribes via an OpenAI-compatible speech-to-text API in ~10 min parts cut at quiet points, with retries and resume after failures - Summarizes the transcript with Claude into meeting notes (decisions, action items, topics with timestamps), streamed to and from the card - Copies the notes to Nextcloud over WebDAV - Shows recording/processing state on the 0.85" LCD and the LED ring - Works around the board's SD card failing multi-sector reads Credentials live in VoiceNotes/secrets.h, which is git-ignored; see secrets.example.h. Also adds the Microsoft CDM customer service SQL implementation (DDL, sample data, reporting queries and docs). Its README is renamed to CDM_README.md so the repository README stays at the top level. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
150 lines
8.0 KiB
Markdown
150 lines
8.0 KiB
Markdown
# VoiceNotes — voice recorder + AI notes for the Waveshare ESP32-C6-LCD-0.85
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Record meetings (up to 4 hours) or voice memos to the microSD card. Then, with one
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button press, the device transcribes the newest recording and has Claude turn it into
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meeting notes: decisions, action items and topics. The notes are saved on the card.
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## Buttons
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The board has **two** usable buttons (BOOT and PLUS). The PWR key is wired to the
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power-switch chip, so the firmware can't read it. "Button 3" is a long-press:
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| Action | Press | What happens |
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|---|---|---|
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| Button 1 – record | **PLUS** click | Starts a new recording |
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| Button 2 – stop | **BOOT** click | Stops and saves the WAV file |
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| Button 3 – AI notes | **PLUS** hold 1 s | Transcribes the latest recording and writes a summary |
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If you'd rather have a real third button, wire a push-button from a free GPIO to
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GND and set `PIN_BTN_EXTRA` in `config.h`.
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## Files on the microSD card
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```
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/recordings/REC_2026-10-02_14-30-05.wav 16 kHz mono 16-bit WAV
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/recordings/last.txt remembers the newest recording across reboots
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/notes/REC_2026-10-02_14-30-05_transcript.txt transcript, with [hh:mm:ss] markers every ~10 min
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/notes/REC_2026-10-02_14-30-05_transcript.progress only while a transcription is unfinished (used to resume)
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/notes/REC_2026-10-02_14-30-05_summary.md Claude's notes: summary, decisions, action items, topics
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```
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The timestamp comes from NTP over Wi-Fi (the ESP32-C6 has no battery-backed
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clock). If Wi-Fi isn't up when you record, the file is named `REC_nodate_xxxxxxxx.wav`.
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## Nextcloud
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When the notes are ready, the summary and transcript are also copied to your Nextcloud over
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WebDAV, into `NEXTCLOUD_FOLDER` (the folder is created if it doesn't exist). Set it up in `secrets.h`:
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```c
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#define NEXTCLOUD_HOST "nc.example.com"
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#define NEXTCLOUD_USER "you@example.com"
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#define NEXTCLOUD_PASSWORD "xxxxx-xxxxx-xxxxx-xxxxx-xxxxx" // an app password
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#define NEXTCLOUD_FOLDER "secondbrain"
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```
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Use an **app password**, not your login password. Create one in Nextcloud under
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**Settings → Security → Devices & sessions → Create new app password**. It works even with
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two-factor authentication on, and you can revoke it without changing your main password.
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If the copy fails, the notes are still on the SD card. Holding PLUS again retries only the
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Nextcloud step; it doesn't redo the transcription or the summary. To regenerate a summary, delete
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its `_summary.md` from the card first.
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## What the screen and LED ring show
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| State | Screen | LED ring |
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|---|---|---|
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| Starting | Mic logo, "Connecting Wi-Fi…" | Amber spinner |
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| Ready | "Ready", time of the last recording | Slow blue breathing (amber if Wi-Fi is down) |
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| Recording | Blinking ● REC, timer (h:mm:ss after an hour), scrolling level meter | Red VU meter that moves with your voice |
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| Saved | ✓, date/time, length and size | Green flash |
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| Uploading | Progress bar, "Part 3 of 12" and % | Blue ring fills up with overall progress |
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| Transcribing | Cyan spinner, part number | Cyan spinning comet |
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| Summarizing | Purple spinner, characters received | Two purple comets |
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| Saving to Nextcloud | Green spinner | Green spinning comet |
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| Done | ✓ "Notes saved", file name or "Also saved to Nextcloud" | Green pulse |
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| Error | ✗ and the reason | Red blinking |
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| No microSD | Red card icon | Slow red blink |
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The status bar shows the clock, the SD card, and Wi-Fi bars.
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## Setup
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1. **Arduino IDE 2.x** with the **esp32 core 3.x** by Espressif (Boards Manager).
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2. Install these libraries from Library Manager:
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*GFX Library for Arduino* (moononournation), *FastLED*, *OneButton*, *U8g2*, *ArduinoJson* (v7).
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3. Copy `secrets.example.h` to `secrets.h` and fill in:
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- your Wi-Fi SSID and password, and your timezone,
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- a speech-to-text API key (`STT_*`). Any OpenAI-compatible
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`/audio/transcriptions` endpoint works: OpenAI (`whisper-1`, `gpt-4o-transcribe`) or Groq.
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- an Anthropic API key for the summary (`ANTHROPIC_API_KEY`).
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4. Board settings (**Tools** menu):
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- Board: **ESP32C6 Dev Module**
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- USB CDC On Boot: **Enabled** (so Serial Monitor works over USB-C)
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- Flash Size: **8MB**
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- Partition Scheme: **8M with spiffs (3MB APP/1.5MB SPIFFS)**
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5. Put a **FAT32** microSD card in the slot, then upload.
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From the command line:
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```bash
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arduino-cli compile --upload -p /dev/cu.usbmodem* -b esp32:esp32:esp32c6:CDCOnBoot=cdc,FlashSize=8M,PartitionScheme=default_8MB .
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```
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Open the Serial Monitor at 115200 baud to see state changes and any API errors. You can also send:
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`p` (same as holding PLUS), `n` (print the latest transcript and summary), `d` (list recordings),
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`s` (SD read test), and `u<file name>` (choose which recording `p` and `n` use).
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## How it works
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| File | Role |
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| `VoiceNotes.ino` | Setup, buttons, state machine |
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| `audio.cpp` | ES7210 mic codec setup over I2C, I2S capture task, WAV writer |
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| `cloud.cpp` | HTTPS: streams the WAV to speech-to-text, then streams Claude's reply into `summary.md` |
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| `ui.cpp` | 128×128 screens (drawn off-screen, then pushed to the LCD) and LED ring animations |
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| `config.h` | Pin map and limits |
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- **Audio:** the two onboard mics go through the ES7210 ADC at 16 kHz and are mixed to mono.
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A high-priority task fills a 2-second RAM buffer, and the main loop writes that buffer to the card.
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This way a slow SD write can't make the recording skip.
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- **Shared SPI bus:** the LCD and the microSD use the same SPI pins, so every access takes `spiMutex`.
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- **Long recordings:** the WAV header is updated every 10 s, so a power cut mid-meeting still leaves a
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playable file. Recording stops at 4 hours (`MAX_RECORD_SECONDS`), or earlier if the card is nearly full.
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- **Transcription in parts:** speech-to-text APIs accept at most 25 MB per file, so the recording is sent
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in ~10-minute parts (`STT_SEGMENT_SECONDS`). Each part is cut at the quietest moment in the 15 s before
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the target, so no word is split. The end of the previous part's text is sent as a hint, so names and
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spellings stay consistent. Each part is streamed straight from the card.
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- **Resume:** each part is retried up to 3 times. If it still fails (for example, Wi-Fi drops), the
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finished parts are kept, and holding PLUS again continues from where it stopped.
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- **SD reads** use 512-byte (single-sector) reads. On this board the microSD fails multi-sector reads.
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- **Summary:** `POST /v1/messages` to `claude-opus-5-5` with streaming. A 2-hour transcript (~100 KB) is too
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big for the board's RAM, so the request body is streamed from the card, and the reply is written to the
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card as it arrives.
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The request sets `fallbacks: "default"` (beta `server-side-fallback-2026-07-01`). If the model declines,
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the API retries on a fallback model instead of failing.
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- If the transcript was saved but the summary step failed, a long-press again reuses the
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saved transcript and doesn't upload the audio a second time.
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## Limits and notes
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- Recordings use about **115 MB per hour** (16 kHz mono WAV). A 2-hour meeting is ~230 MB.
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- Processing a 2-hour meeting takes roughly **15–25 minutes**: 12 parts, each about a minute to upload at
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~300 KB/s plus 20–40 s to transcribe, then a minute or two for Claude. The device can't record while it's
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processing.
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- For multi-hour meetings, run the device from USB power. A small battery won't last.
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- Privacy: your audio goes to the speech-to-text provider, and the transcript goes to Anthropic.
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- TLS certificates are verified with the ESP32 core's built-in CA bundle.
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## Troubleshooting
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| Symptom | Fix |
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| LED colours wrong (red shows green) | Set `LED_COLOR_ORDER` to `GRB` in `config.h` |
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| Recordings are quiet or noisy | Change `MIC_GAIN_STEP` in `config.h` (10 = 30 dB) |
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| "Microphone init failed" | The ES7210 didn't answer at I2C 0x40. Power-cycle the board |
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| `STT HTTP 401` / `Claude HTTP 401` | Check the API keys in `secrets.h` |
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| File names say `nodate` | Wi-Fi/NTP wasn't ready yet. Wait for the clock in the status bar |
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| Serial warns that audio was dropped | Use a faster (Class 10 / U1) microSD card |
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