STUDIO — Cardputer Music Machine

A self-contained groovebox firmware for the M5 Cardputer (ESP32-S3, ES8311 codec) — synth + sequencer + sampler + microphone recorder + song library, all in one firmware. No M5Unified dependency: uses LovyanGFX for the screen, a small I2C driver for the keyboard, and the legacy ESP-IDF i2s driver for ES8311 record/playback (so the mic actually records).

Quick Start — just flash it

Don't want to install a build environment? Grab the prebuilt firmware.

1. Go to the Releases page and download cardputer-studio-v1.1.bin.
2. Flash it to your Cardputer at offset 0x0 with M5Burner (GUI) or esptool:

   esptool.py --chip esp32s3 --port <PORT> --baud 921600 write_flash 0x0 cardputer-studio-v1.1.bin
   

3. Set up the SD card (FAT32/exFAT):
   • Download cardputer-studio-drums-v1.1.zip from the release and unzip it.
   • Put the whole drums folder at the card root → <card>/drums/BD808.wav …
   • Insert the card and reset. /samples (your recordings) and /songs (saves) are created automatically.

The drum kits read their samples from /drums; if a file is missing that pad falls back to a synth drum. Recordings, samples and songs all live on the card.

Quick reference card

A one-page printable key map: English · 中文

Features

• SYNTH / sequencer — 2 melodic tracks (A/B) + 8-pad drum track + a phrase track that plays a trimmed slice of a long recording.
  • Wavetable voices (saw / square / triangle / sine), tone (brightness) control
  • 6 drum kits (1 cycles): ACOU (synth) + real-sample 808 / 909 / acoustic / lo-fi / retro, loaded from /drums
  • Per-step note length, accent/velocity, slide, probability, chords, swing
  • Per-track effects: delay, octave, sub, fifth, chorus; master space FX (echo / reverb)
  • Live FX: bitcrush, tape-stop, arpeggiator, reverse
  • Phrase track per-step controls: stack effects (OCT/SUB/CHO/DLY/REV/STUT), movable window, length, pitch
  • 16 song save slots (saved to SD, including the drum-kit choice)
• SAMPLER — play any 16-bit WAV on the SD card pitched across the keyboard; trim + effects (normalize, reverse, lo-fi, drive, fade) saved as a new sample, with a preview that plays the processed result
• RECORDER — record the mic straight to SD (streamed, low RAM), play back
• SONGS — browse / preview / rename / open saved songs
• LIBRARY — browse / play / delete / rename recordings

Hardware (Cardputer Adv / ESP32-S3)

• Display: ST7789 on SPI2 (sclk 36, mosi 35, dc 34, cs 37, rst 33)
• Keyboard: TCA8418 on internal I2C (SDA 8, SCL 9, addr 0x34)
• Codec: ES8311 on internal I2C (addr 0x18); I2S BCLK 41, LRCK 43, DIN 46, DOUT 42
• SD card: separate SPI (sck 40, miso 39, mosi 14, cs 12)

Build

Arduino + arduino-cli with the ESP32 core:

arduino-cli compile --fqbn esp32:esp32:esp32s3:PSRAM=disabled,FlashSize=8M,PartitionScheme=default_8MB studio
arduino-cli upload  -p <PORT> --fqbn esp32:esp32:esp32s3:PSRAM=disabled,FlashSize=8M,PartitionScheme=default_8MB studio

Drum-kit WAVs go in /drums on the SD card; put your own 16-bit PCM WAVs in /samples for the sampler / phrase sources.

Controls

Press ctrl inside SYNTH for the on-device key map. Menu: 1 SYNTH · 2 SAMPLER · 3 RECORDER · 4 SONGS · 5 LIBRARY · ` back.

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Made on a Cardputer, for fun. 🎛️

Made by Yuan · GitHub

Licensed under the MIT License.