Build & Customise OpenWrt for Raspberry Pi

OpenWrt Raspberry Pi Subtarget

OpenWrt is an open source operating system based on Linux especially designed for embedded & networking devices. This OS is well known for its lightweight footprint, standardized configuration approach (using LUCI interface), easy to build images, as opkg packages. At the core of OpenWrt is a writable root file system, where the users can add and/or remove packages, modify configs etc…. without having to re-flash the entire firmware/operating system. This is achieved by overlaying a read-only compressed SquashFS file system with a writable JFFS2 filesystem using OverlayFS. You can install pre-built packages from OpenWrt repo (which contains approximately 3500 packages) using opkg package manager. The Build Process Below steps cover the required pre-build environment and how to build OpenWrt from the source tree for Raspberry Pi board. Even though OpenWrt recommends Debian for the build machine, I built it successfully on Ubuntu 18.04 Desktop. Setup Build Environment

Build OpenWrt […]

$2 Wemos W600-PICO WiFi IoT Board Ships with MicroPython Firmware

Wemos W600-PICO

Wemos has designed some great WiFi IoT boards over the last few years with products like Wemos D1 mini or Lolin32 based on Espressif Systems ESP8266 and ESP32 processors respectively. But the company has recently launched its cheapest board ever, with W600-PICO board going for just $2.10 + shipping. The board is based on Winner Micro W600 Arm Cortex-M3 WiSoC, and comes pre-loaded with MicroPython firmware. Wemos W600-PICO V1.0.0 specifications: SoC – Winner Micro W600 Arm Cortex-M3 MCU @ 80MHz with 1MB Flash Wireless Connectivity – 2.4GHz 802.11 b/g/n WiFi 4 up to 150 Mbps USB – 1x Micro USB port for power and programming (via CH340 USB to TTL chip) Expansion – 2x 10-pin headers with 15x GPIO, 9x PWM, 1x I2C, 1x SPI, 1x UART, Wake Up, Reset, 5V, 3.3V, and GND signals; 3.3V I/O voltage. Misc – Reset button Power Supply – 5V via micro USB port […]

ArmSoM RK3588 AIModule7 NVIDIA Jetson Nano-compatible SOM

Xiaomi Redmi AC2100 Router Sells for $35 and Up

Xiaomi Redmi AC2100 Router

Xiaomi has launched several affordable WiFi routers over the years. Their latest model is called Xiaomi Redmi AC2100 Router and comes with a dual-core, quad-thread MIPS processor, 128MB storage, WiFi 5 with 6 antennas, and four Gigabit Ethernet ports. Xiaomi Redmi AC2100 router specifications: Processor – MediaTek MT7621A dual-core/quad-thread MIPS processor @ 880MHz System Memory – 128MB RAM Storage – 128MB flash Connectivity Wireless 2.4GHz 2×2 Wi-F 802.11n @ 300Mbps 5G 4×4 WiFi 802.11ac @ 1733Mbps 6x external high gain (5dBi) antennas Security – WPA-PSK / WPA2-PSK encryption, wireless access control (black and white list), hidden SSID, intelligent anti-scratch network Ethernet 1x 10/100/1000Mbps WAN (Auto MDI/ MDIX) 3x 10/100/1000Mbps LAN (Auto MDI/ MDIX) Misc – 2x LEDs Indicators (Internet and System), Reset pin hole Power Supply – 12V/2A Dimensions – 259 x 176 x 184mm The router is said to come with MiWiFi firmware based on OpenWrt with “deep customization”, […]

SimplePnP is a Low-Cost, Open Source Hardware Pick-and-Place Machine (Crowdfunding)

SimplePnP OSHW Pick-and-Place Machine

If you have a small production run for your board, it may not be cost-effective to ask a factory to manufacture it for you, and assembling the boards entirely by hand will be a time-consuming process. Getting a pick-and-place machine to automate the process would save time, but even the cheaper models on Aliexpress cost several thousand dollars. Citrus CNC tries to address the cost issue with the SimplePnP open source hardware pick-and-place machine that brings the price down to several hundred dollars. SimplePnP key features and specifications: MCU – Microchip Atmega328p running GRBL firmware Motor Drivers – TMC2209 stepper for two-phase stepper motors Word Area – 300 mm (X) x 300 mm (Y) Z Travel – 23 mm Components per Hour – 750 with vision assist Component Size – As small as 0402 (1005 metric) Vacuum Heads – Single vacuum head (base model), or optional dual-head Nozzle System – […]

Seeeduino XIAO is a Tiny Arduino Zero Compatible Board with Battery Support

Seeeduino XIAO

Seeeduino XIAO is the smallest Arduino compatible board from SeeedStudio’s Seeduino family. Measuring just 23.5×17.5 mm, the board is equipped with Microchip SAMD21 Arm Cortex-M0+ microcontroller and exposes various digital and analog I/Os. Seeduino XIAO specifications: MCU – Microchip SAMD21G18 ARM Cortex-M0+ microcontroller at up to 48MHz with 256KB Flash,32KB SRAM USB – 1x USB type C port for power and programming Expansion I/Os 2x 7-pin headers with 11x analog inputs, 11x digital I/Os, 1x DAC, SPI, UART, and I2C 3.3V I/O voltage (not 5V tolerant) Misc – 1x user LED, power LED, 2x LEDs for serial port downloading, Reset pads, SWD pads, 32.768KHz crystal oscillator Power Supply – 5V via USB-C power, power pads (VIN/GND) for battery Dimensions – 23.5×17.5×3.5 mm All main components are placed under a shield, but there may be some charger chip (nope: see comments) as the company explains the board supports batteries via the […]

NComputing RX420(HDX) Raspberry Pi 4 Thin Client Works with Citrix HDX

RX-420 HDX Raspberry Pi 4 Thin Client

NComputing RX300 Raspberry Pi 3 thin client was launched in 2017 with support for the company’ vSpace Pro desktop virtualization solution for Linux and Windows, and I tested it accessing a Windows Server 2006 host located in Singapore, and performance was pretty good for a remote system as I could play 1080p YouTube videos, browse multiple tabs in Chrome, etc.. relatively smoothly.  This type of solution is aimed at businesses, for which it may be easier and cheaper to handle a fleet of devices using thin clients and servers, instead of traditional PC’s. Beside its vSpace Pro RX300 thin client, NComputing also introduced another Raspberry Pi 3 thin client that same year with RX-HDX using a design similar to RX300 but instead integrating support for Citrix HDX virtualization technology. NComputing now unveiled an update for the latter with RX420(HDX) thin client based on Raspberry Pi 4 SBC with 2GB RAM. […]

Rockchip RK3568, RK3588 and Intel x86 SBCs and SoMs in 2025

Virtual Desktop and Oculus Quest Tips & Tricks

oculus quest

Hey, Karl here. I wanted to share some experimenting I did with the Oculus Quest we purchased as a family gift for Christmas. One of the features I was looking forward to was wirelessly streaming VR games from my PC.  It is not officially supported by Oculus but Virtual Desktop allows you to do this. Virtual Desktop is an app that can be purchased through the Oculus store. Unfortunately, there are a couple of steps that need to be taken to stream VR to the headset. Oculus forced VD to remove the emulated VR feature in its official store version. Once it is purchased you can then sideload the emulated VR version through Side Quest. Side Quest is a simple tool that makes sideloading apps easy and has a bunch of demo and games that aren’t in the Oculus store. The instructions are easy to follow on the Side Quest […]

STMicro STM32WL is the World’s First LoRa SoC

There is no denying that the Internet of Things is going to disrupt a lot of markets and it’s already happening to some extent. The question being asked is: “What IoT connectivity technology will lead this disruption era?”. One major technology in this connectivity race is LoRa. LoRa’s long-range, low-power, small footprint, simplicity, and the amazing community backing it, have allowed it to find its way into various applications while gaining for the top LPWAN IoT connectivity technology. STMicroelectronics, one of the biggest semiconductor manufacturer, also believes in the potential of LoRa with the launch of STM32WL, making it the World’s first die-integrated LoRa System-on-Chip. Traditional LoRa embedded platforms usually involve the need for a separate MCU chip and different LoRa transceiver chips either coupled together in one single package or separately. This undoubtedly adds extra design complexity, size, and even cost. STMicro hopes to address this with their STM32WL SoC. […]

Boardcon CM3588 Rockchip RK3588 System-on-Module designed for AI and IoT applications