M5Stamp C3 RISC-V board supports WiFI 4, Bluetooth 5.0 Long Range and 2 Mbps bitrate

M5Stamp C3

It was only last month that M5Stack launched the M5Stamp Pico module based on an ESP32-PICO-D4 SiP and heat-resistant plastic shell, but M5Stamp C3 board is already out with most of the same specifications and features but an ESP32-C3 RISC-V SoC replaces the ESP32 dual-core Xtensa processor. M5Stamp C3 offers WiFi 4 and Bluetooth 5.0 with high bitrate and long-range connectivity and comes with the same heat-resistant plastic shell, but the company also highlights the RSA-3072-based secure boot and the AES-128-XTS-based flash encryption as a more secure way to address Bluetooth security concerns. M5Stamp C3 specifications: WiSoC – ESP32-C3FH4 32-bit single-core RISC-V processor @ up to 160 MHz, with 384KB ROM, 400KB SRAM, 8KB RTC SRAM, 4MB embedded flash, WiFI and Bluetooth Connectivity 2.4 GHz WiFi 4, 20 MHz and 40 MHz bandwidth, IEEE 802.11 b/g/n protocol, up to 150 Mbps Bluetooth 5, Bluetooth mesh, with supports for 125 Kbps, […]

WattUp 1W active energy harvesting developer kit enables at-a-distance wireless charging

WattUp 1W Active Energy Harvesting Transmitter

Two years ago, we noted Energous’ WattUp hearables developer kit that would charge earbuds with the company’s WattUp near-field wireless charging technology. The company has now introduced the WattUP 1W active energy harvesting developer kit capable of charging multiple IoT devices with at-a-distance wireless charging. The kit is said to be “active” because there’s a 6-inch transmitter, let’s call it a power gateway, and several IoT devices that harvest energy from it. Traditional passive solutions will harvest ambient energy from the surrounding environment, and may not deliver enough power, and do so unpredictably. The developer kit comes with the transmitter, plus one or more receiver units, and relies on the following main chips: Transmitter Dialog Semiconductor DA14682 SmartBond Bluetooth 5.0 Cortex-M0 SoC Dialog Semiconductor DA4100 Wireless Power Transmitter SoC Dialog Semiconductor DA3210 1W Power Amplifier A discrete rectifier and a DA2210 WPT rectifier Receiver(s) Dialog Semiconductor DA14531 Cortex-M0+ BLE 5.1 […]

Portenta H7 Lite Connected brings back WiFi & Bluetooth

Portenta H7 Lite Connected

Arduino has launched another Arduino Pro board! Well, sort of. Let’s not get too excited. The Portenta H7 Lite Connected is based on last month’s Portenta H7 Lite that itself was a cost-optimized version of Portenta H7 board without a wireless module, USB-C video output, and only fitted with the lower cost Microchip ATECC608 secure element. Portenta H7 Lite Connected is exactly the same board, except it brings back the Murata 1DX module with 2.4GHz 802.11b/g/n WiFI 4 and Bluetooth 5.1 BR/EDR/LE connectivity, plus the related u.FL antenna connector. Portenta H7 Lite Connected specifications: Microcontroller – STMicro STM32H747XI Cortex-M7 @ 480 MHz + M4 @ 200 MHz MCU  with 2MB dual-bank Flash memory, 1 MB RAM, Chrom-ART graphical hardware accelerator System Memory – 2MB SDRAM (upgradeable up to 64MB) Storage – 16MB QSPI NOR Flash (Upgradeable up to 128MB) Connectivity 2.4GHz WiFi 802.11b/g/n up to 65 Mbps and Bluetooth 5.1 […]

ZB-GW03 ESP32-based Ethernet Zigbee gateway works with Tasmota firmware

ZB-GW03 ESP32 Ethernet Zigbee Gateway

ZB-GW03 is an Ethernet Zigbee Gateway compatible with eWelink mobile app and with a design similar to SONOFF ZBBridge gateway but replacing ESP8266 SoC by ESP32 SoC, and adding an Ethernet port. The ZB-GW03 gateway is apparently based on the same Silicon Labs EFR32MG21 Zigbee Arm Cortex-M33 chip and has been hacked to run Tasmota open-source software for people preferring more flexibility and/or integration with OpenHAB or Home Assistant open-source home automation frameworks via Zigbee2MQTT. ZB-GW03 gateway specifications: Main MCU – Espressif Systems ESP32 dual-core Tensilica TX6 processor @ 240 MHz with WiFi 4 and Bluetooth connectivity Zigbee MCU – Silicon Labs EFR32MG21 Arm Cortex-M33 MCU @ 80 MHz with Zigbee 3.0 connectivity Connectivity 10/100M Ethernet, WiFi, and Bluetooth via ESP32 Zigbee 3.0 via Silabs MG21 MCU with support for 128 nodes, up to 200+ meter range One 2.4 GHz Zigbee antenna One 2.4 GHz PCB antenna for WiFi Misc […]

BrakTooth vulnerabilities impact closed-source Bluetooth stacks used in chips from Espressif, Intel, Qualcomm…


BrakTooth is a family of new security vulnerabilities in commercial, closed-source Bluetooth Classic stacks that range from denial of service (DoS) via firmware crashes and deadlocks to arbitrary code execution (ACE) in certain IoT devices. A team from Singapore has discovered 16 new security vulnerabilities after evaluating 13 Bluetooth devices from 11 vendors, but after browsing through the list of certified Bluetooth devices with impacted processors, they estimate it could impact 1400 devices. We can see the list of BrakTooth-impacted SoCs include some familiar names like Intel AX200 (found in many laptops and computers through M.2 cards), Espressif Systems ESP32, Texas Instruments CC2564C, Qualcomm CSR8811/CSR8510, Bluetrum AB32VG1 board (based on AB5301A SoC) which I’ve just reviewed, and more… The good news is that most vendors have either already submitted a patch or working on it. Espressif, Infineon (previously Cypress), and Bluetrum already have released patchsets for their firmware. It’s really […]

Getting started with Bluetrum AB32VG1 RISC-V Bluetooth audio board using RT-Thread

Bluetrum AB32VG1 RISC-V Bluetooth audio board

Bluetrum AB32VG1 is a development board based on AB5301A RISC-V microcontroller designed for Bluetooth audio applications as well as general-purpose projects that works with RT-Thread real-time operating system. RT-Thread sent me a board for review, and I’ll write about my experience in a getting started guide for Bluetutm AB32VG1 trying out the RT-Thread Studio IDE with the LED blink and audio samples, as there’s no Bluetooth sample at this time… Bluetrum AV32VG1 Unboxing The board ships with a USB-C cable for power and programming. It offers Arduino UNO headers for expansion, a MicroSD card slot, a USB host port, a 3.5mm audio jack, an IR receiver, and a few buttons. There’s nothing to do on the bottom of the board apart from a QR Core for the WeChat app. There are also several configuration jumpers, but I could not find any documentation about these and did not mess with the […]

25-key ESP32 Touch Matrix makes good use of ESP32’s touch sensor interface

ESP32 Touch Matrix

Besides the addition of Bluetooth, there are many differences between ESP8266 and ESP32 and one of the lesser-known interfaces may be ESP32’s touch sensor interface. India-based Electro Point’s ESP32 Touch Matrix makes good use of the touch sensor interface with 25 touch pads arranged in a 5×5 matrix creating a wireless keypad that could connect over WiFi or Bluetooth to a host. ESP32 Touch Matrix board specifications: Wireless module – ESP32-WROOM-32U with Espressif ESP32-D0WD dual-core Tensilica processor, 32Mbit SPI flash, 2.4 GHz WiFi, and Bluetooth LE connectivity 25 keys arranged in a 5×5 matrix Expansion – 4-pin I2C header for expansion, e.g. an OLED display Programming – Programming headers Misc – RGB status indicator, EN button Power Supply – 5V input via 2-pin header; built-in 3.3v regulator for ESP32 Dimensions – TBD When a capacitive load, such as a human hand) is in close proximity to the sense-pad, the sensor […]

Bluetooth 5.3 new features lower latency, interference, improve battery life, security

Bluetooth 5.3 Channel Classification Enhancement

Bluetooth 5.3 Core Specification was adopted on July 13, 2021, without fanfare, and the only related announcement that I could find is CEVA RivieraWaves Bluetooth IP getting support for Bluetooth 5.3. Bluetooth 5.3 brings four new features or enhancements and removes one extension from the core specification: Periodic Advertising Enhancement – The AdvDataInfo (ADI) field of the common extended advertising payload format may now be included in AUX_SYNC_IND protocol data units (PDUs) which are broadcast when a device is performing periodic advertising. The Bluetooth Low Energy (LE) controllers may now use the information in the ADI field to recognize packets that contain retransmitted copies of identical or semantically equivalent data, and discard those packets in order to prevent unnecessary processing on the nodes, and make sure the overall throughput is not affected due to retransmitted packets. Encryption Key Size Control Enhancement – In Bluetooth BR/EDR, encryption key sizes are negotiated […]