GUITION has a new version of its rotary knob with a built-in round touchscreen. The JC3636F118C-I-YR1 swaps the ESP32-S3 of the earlier JC3636K518C for Espressif's ESP32-S31, which brings Wi-Fi 6 and an 802.15.4 radio for Zigbee and Thread. CNX Software wrote it up on 22 October 2026 after a reader pointed it out, and the knob is already listed on AliExpress.

What is inside

The chip is an ESP32-S31NRV16. It has a high-performance RISC-V core at 320 MHz with an FPU and SIMD instructions, a separate low-power RISC-V core, 512 KB of SRAM, 32 KB of low-power SRAM and 16 MB of PSRAM. On the radio side there is 2.4 GHz Wi-Fi 6, Bluetooth 5.4 (LE Audio, direction finding, Bluetooth Mesh 1.1 and Classic) and the 802.15.4 radio for Zigbee, Thread and Matter. Program storage is 16 MB of flash, with a microSD slot for media and Wi-Fi settings.

The screen is a 1.8-inch round TFT with 360x360 pixels, driven by an ST77916 over SPI, with a CST816 capacitive touch controller and adjustable backlight. Around it sits a CNC-machined knob with haptic feedback from a DRV2605L driver. A PCM5100A drives the built-in speaker, and there is a MEMS microphone.

Power comes in at 5 V over USB-C, with an optional battery whose capacity GUITION does not list. The knob draws about 1.3 W, measures 66 mm across and 22 mm high, and weighs about 160 g. One oddity: the USB-C port cares which way round the plug goes. With the notch facing up it is in file transfer mode, with the notch down it is in firmware programming mode.

Firmware and what you can build on

Out of the box it runs a clock, a countdown timer, a music player, an MJPEG and AVI video player, a photo frame, a spectrum analyser for audio, Bluetooth and USB audio, and a USB HID mode in which the knob controls the volume on a computer.

GUITION mentions development in the Arduino IDE, ESP-IDF and MicroPython, but the download CNX Software checked has only ESP-IDF 6.1.0 samples: the demo firmware, an LVGL music and MJPEG player and the Xiaozhi voice assistant. The Arduino folder is empty. The package also includes basic instructions, datasheets and PDF schematics.

For smart home builders, the new radio is the main reason to look at this version over the S3 one, which has no 802.15.4. Keep expectations in check, though. None of the supplied samples does anything with Zigbee or Thread, and CNX Software notes that the ESP32-S31 is new, so its firmware support is less mature than the S3's. The other gains are faster cores, a 2D graphics engine, a hardware MJPEG decoder and 480 Mbps USB 2.0.

Price

GUITION sells the JC3636F118C-I-YR1 for $40.09 on AliExpress with the battery and $38.49 without it. Both prices include shipping but not taxes. The older ESP32-S3 model, JC3636K518C, was listed at $39.13 with a battery when CNX Software checked, so the upgrade costs about a dollar more.