Espressif's ESP32-S31 is starting to show up in hardware you can buy. On October 22, 2026, CNX Software reported that GUITION has moved its round-display rotary knob from the ESP32-S3 to the new chip. The product is the JC3636F118C-I-YR1, a 1.8-inch touchscreen inside a CNC-machined knob with haptic feedback. CNX lists it on AliExpress at $40.09 shipped with a battery and $38.49 without one, excluding taxes. Eight days earlier, CNX covered Viewe's 4.3-inch display board, which it described as apparently the first third-party development board built on the S31.
Two boards don't make an ecosystem. Still, two display-centric products in the same month suggest board vendors are designing the S31 into human-interface hardware, and that use case lines up with what Espressif built into the chip.
The silicon: what Espressif says the S31 is
Espressif's ESP32-S31 product page describes a dual-core 32-bit RISC-V SoC running at up to 320 MHz. The company rates it at 6.86 CoreMark/MHz and lists an MMU. One core has a 128-bit data path with SIMD. On-chip memory is 512 KB of SRAM, and the chip supports 8-bit DDR PSRAM at 250 MHz. Espressif lists 60 GPIOs.
The radios are the headline. Espressif lists:
- Wi-Fi 6 (802.11ax), 2.4 GHz
- Bluetooth 5.4 LE with LE Audio, Direction Finding and Mesh 1.1, plus Bluetooth Classic
- IEEE 802.15.4 for Thread and Zigbee
The chip also has a 1000 Mbps Ethernet MAC. LE Audio and Classic on the same part is worth noticing. It lets a single chip handle legacy audio sinks and newer LE Audio devices, which matters for the knob's Bluetooth-audio mode described below.
The multimedia blocks explain why the first boards both have screens. Espressif lists a DVP camera interface, a parallel LCD interface (RGB, I8080 and MOTO6800), a JPEG codec, a PPA (pixel-processing accelerator) and 2D-DMA, plus up to 14 capacitive touch sensing channels. Security features include a TRNG, a RAM-based PUF, secure boot, flash and PSRAM encryption, AES, RSA, ECDSA and ECC accelerators, a TEE and APM.
Watch the tense on software. Espressif says the S31 "will be supported" in ESP-IDF, ESP-Matter, ESP-BLE-AUDIO and ESP-GMF. The vendor page frames this as forthcoming support, not a finished release, so early adopters should expect to be working against a moving SDK.
The knob: GUITION JC3636F118C-I-YR1
GUITION's own product page could not be read for this article, so every board-level spec and price below comes from CNX Software's write-up.
CNX says the knob uses an ESP32-S31NRV16. It describes the CPU as an RV32IMAFCP high-performance core at 320 MHz with FPU and SIMD, plus a low-power core, with 512 KB SRAM and 32 KB LP SRAM. The board adds 16MB of PSRAM and 16MB of flash. The radio set matches Espressif's: Wi-Fi 6, Bluetooth 5.4 (LE Audio, direction finding, Mesh 1.1, Classic) and 802.15.4 for Zigbee, Thread and Matter. There is a microSD slot.
The display is a 1.8-inch round 262K-color TFT at 360x360. It is driven by an ST77916 over SPI, with a CST816 capacitive touch controller. Audio goes out through a speaker fed by a PCM5100APWR, and input comes from an MSM261D4030H1CPM MEMS microphone. A DRV2605L haptic driver provides the knob's tactile feedback.
USB-C handles power and data, and CNX notes one unusual detail: which way you plug in the reversible connector decides whether the board enters file-transfer mode or programming mode. Power is 5V over USB-C, and an optional rechargeable battery is offered, though CNX says its capacity isn't listed. CNX puts typical power at about 1.3 W. The unit measures 66 mm in diameter by 22 mm and weighs about 160 g.
Firmware out of the box
According to CNX, the knob ships with a clock, timer, music player, MJPEG/AVI player, photo frame, spectrum analyzer, Bluetooth audio, USB audio and a USB HID volume control. The downloadable package includes ESP-IDF 6.1.0 samples: LVGL music and MJPEG demos and a Xiaozhi voice assistant. It also contains an Arduino folder that CNX found empty. GUITION claims support for the Arduino IDE, ESP-IDF and MicroPython. With the Arduino folder empty at the time of CNX's report, ESP-IDF is the only path with actual example code.
The display board: Viewe PLCM-UES31S043H800V480C-U
On October 14, 2026, CNX Software covered Viewe's PLCM-UES31S043H800V480C-U and called it apparently the first third-party development board on the ESP32-S31. Where the knob puts the chip directly on the board, Viewe uses Espressif's ESP32-S31-WROOM-3-N16R16V module, which carries 16MB of flash and 16MB of PSRAM.
Per CNX, the board has a 4.3-inch 800x480 IPS RGB display (ST7262E43-G4, GT911 touch). That puts the S31's parallel RGB LCD interface to work, where the knob's panel runs over SPI. I/O includes USB-C, a high-speed USB 2.0 Type-A port, microSD, RS485 and CAN, and a 2x10-pin GPIO header. Audio uses an ES8389 codec, two NS4150B amplifiers and two microphones. CNX lists a 5V supply, 320 mA typical and 500 mA maximum current draw, a -20 to +70 °C operating range, and a 105 x 67 mm footprint. CNX notes the S31 is still a preview device, so the board can be programmed only with ESP-IDF, using the master branch with the --preview flag. As of CNX's October 14, 2026 report, the board was sold for $38.99 on the VIEWE store, with an AliExpress listing expected within days.
CircuitPython gets an early port
On the software side, the CircuitPython 11.0.0-alpha.2 release notes (October 21, 2026) add "Espressif ESP32-S31 support" (#11581). The project classes the port as alpha and warns that it "will have bugs and missing functionality." It is a starting point, not a production target, and the notes don't name either of these boards as supported.
What It Means for Makers
Who it's for. The GUITION knob suits anyone building a desk controller, a Home Assistant dial, a media remote or a voice-assistant puck. Those builders previously had to assemble a round display, an encoder, a haptic driver and audio separately, or settle for the ESP32-S3 version. The Viewe board is for HMI panel work: industrial or home-automation front ends that want RS485 and CAN next to an 800x480 screen.
What it replaces. The knob appears to be an update to GUITION's ESP32-S3-based JC3636K518C, which CNX lists at $39.13 with a battery. So the S31 version costs roughly the same ($40.09 with battery) and adds Wi-Fi 6, Bluetooth 5.4 with LE Audio and Classic, and native 802.15.4 for Thread and Zigbee. The 802.15.4 radio is the practical gain. A Matter-over-Thread controller no longer needs a second radio chip, at least on paper, pending the ESP-Matter support Espressif says is coming.
Price and availability. As of CNX's October 22, 2026 report, the GUITION JC3636F118C-I-YR1 is listed on AliExpress at $40.09 shipped with battery or $38.49 without, excluding taxes. The Viewe PLCM-UES31S043H800V480C-U was priced at $38.99 on the VIEWE store as of CNX's October 14, 2026 report.
Caveats. This is early-adopter territory. Espressif describes its SDK support in the future tense, the CircuitPython port is labeled alpha, and the knob's Arduino folder was empty when CNX looked. If you need a mature toolchain today, the S3 version still has the longer track record. If you want the radios, ESP-IDF 6.1.0 and the bundled samples are where to start.
