Made by AI, Directed by David Stein

Search
Creative Hardware

Espressif's ESP-Mosaico Is a Very Good Dev Kit With an AI Claim Nobody at Espressif Made

A 480×480 AMOLED, haptics, battery, two Bosch magnetometers and a new dual-core RISC-V ESP32-S31 — and the vendor's own documentation never mentions AI once.

5 min read

Espressif announced ESP-Mosaico on 20 October 2026, and the specification is genuinely interesting. The framing around it is where this gets worth writing about.

What is on the board

The kit splits into a CoreBoard and a BaseBoard, joined by a 60-pin board-to-board connector. The BaseBoard carries the speaker, the battery and two expansion headers.

  • Display — 2.16-inch, 480 × 480 QSPI touch panel, CO5300 display controller, CST9220-series touch controller over I²C
  • Audio — ES8311 mono codec over I²S, NS4150B 3 W Class-D amplifier, onboard microphone and speaker
  • Haptics — vibration motor on GPIO8
  • Power — 3.7 V, 65 mAh Li-ion cell, TP4057 charger, BQ27220 fuel gauge; USB-C can source 5 V at up to 500 mA
  • Sensors — Bosch BMI270 6-axis IMU and two Bosch BMM150 3-axis magnetometers
  • Storage — 16 MB SPI NOR flash plus a 1 Gbit (128 MB) SPI NAND device for assets
  • Expansion — left and right 2 × 10-pin, 2.54 mm pitch module headers exposing GPIO, UART, I²C, USB Serial/JTAG and power, with additional I²C and power pads on the back

Two expansion modules exist so far: a Camera Module and a Multi-function Interaction Module. There are two CoreBoard revisions, V1.0 and V1.2, identified from the silkscreen.

Two magnetometers is the specification that should make you curious. One gives you a compass. Two, separated in space, give you a gradient — which is how you locate a magnet rather than merely sense a field. Espressif’s own documentation lists “magnetic expansion” among the kit’s target scenarios, and that is almost certainly what the second BMM150 is for: snap a module on and have the host work out which module it is and where.

The chip

The ESP32-S31 is the real news underneath the dev kit, and it has been in mass production since 27 July 2026.

Dual-core 32-bit RISC-V at up to 320 MHz with a floating-point unit and SIMD on one core, plus a separate low-power RISC-V core. 512 KB SRAM, 32 KB low-power SRAM, 16 MB in-package PSRAM. Radios: Wi-Fi 6 on 2.4 GHz, Bluetooth 5.4 with LE Audio, direction finding, Mesh 1.1 and Classic BR/EDR, and an 802.15.4 radio for Zigbee, Thread and Matter.

The peripheral list is what marks it as a media part rather than a sensor part: a JPEG codec, a pixel-processing accelerator, LCD and camera controllers, USB 2.0 High-Speed OTG, an Ethernet MAC, and CAN-FD.

For anyone building installations or instruments, the combination that matters is the pixel accelerator plus the 16 MB of in-package PSRAM plus a 480 × 480 panel. Driving a square AMOLED at a decent frame rate has historically been the thing that pushed a project off an ESP32 and onto a Pi. This is Espressif closing that gap deliberately.

Software support is through ESP-IDF with esp32s31 as the target, and there is a board support package covering display, touch, audio, sensors, battery management, NAND flash, the USB console and the module interfaces.

The AI claim

Here is the discrepancy. The board has been widely covered — including in the headline of the write-up that put it in front of us — as a “modular development platform for AI-assisted hardware creation.” Third-party videos describe it as a board for vibe coding.

Espressif’s own documentation says: “ESP-Mosaico is an expandable smart interaction development kit based on ESP32-S31.” It lists the target scenarios as “magnetic expansion, motion sensing, square touch display, and edge multimedia scenarios.” It does not mention AI. Not in the description, not in the scenarios, not in the feature list. The only trace is a control labelled “Function/AI button” in a third-party spec listing, whose behaviour is deferred to an external Factory Application Guide, and a reference to “edge voice” applications.

So either the AI workflow lives somewhere we have not been able to read, or it is a framing that accreted around a board whose vendor is describing it as a touchscreen dev kit with magnetic modules. We cannot tell you which, and we are not going to assert the headline claim on the strength of coverage when the manufacturer’s documentation declines to make it.

Price, which nobody can agree on

  • A $40 reference price is reported by I-Programmer, which also says demand pushed the first batch toward $100
  • AliExpress third-party listings are reported at about $117
  • A reader comment on one write-up cites $116.75 as 30% off $166.79

Espressif’s own page gives no price and no ordering link — only a sales-questions contact. Nor does it state whether schematics or hardware design files are available, or under what licence, so the openness of the hardware design is unconfirmed. For a company with a strong record of publishing reference designs, that is probably a documentation gap rather than a policy, but it is not something to assume.

One more inconsistency worth recording, since it is the sort of thing that wastes an afternoon: one write-up’s body text gives the module headers as 2 × 10-pin while its own spec table says 2 × 20-pin. Espressif’s documentation says 2 × 10P. Trust the vendor.

Verdict

As a dev kit, this is well put together: a square AMOLED with a proper controller, real audio silicon rather than a buzzer, a fuel gauge rather than a bare charger, haptics, and an expansion scheme with a plausible mechanism behind it. For a desk instrument, a handheld controller, a gallery label or a small interactive object, the parts list is close to ideal and the chip is a meaningful step up.

Buy it for the AMOLED, the pixel accelerator and the magnetic modules. Do not buy it for an AI workflow until somebody shows you the AI workflow.

Sources

Related Reading