Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three […]
Author Archives: DP
DIY Analog resource monitor for your PC
Sasa Karanovic posted detailed instructions of how to build a physical dashboard for your PC, that is available on GitHub: The overall architecture is very simple; There is a python script that is running on a PC and collects CPU, memory, network and GPU usage. Then, it sends that information over serial COM port to […]
The Annoying CAPS LOCK warning buzzer
Glen Akins made a USB notification device that make annoying warning noise when CAPS LOCK is enabled: The only way to make CAPS LOCK even more annoying was to make it audible! Now never type a password in all upper case, join 500 lines together in vi, or turn a harmless forum post into an […]
ATTiny85 Pulse oximeter with photoplethysmogram (PPG) display
tinyPulsePPG, an ATTiny85 Pulse Oximeter with Photoplethysmogram (PPG) display by Jeff Magee: This project implemented on an ATTiny85 displays a moving Photoplethysmogram together with pulse rate and estimates of SpO2 – blood oxygen percentage. It uses an SSD1306 128×32 OLED display and a Max30102 sensor. It is emphasised that this should not be used for […]
Current meter based on ESP-12E and LTC4150
Victor Chew made a simple current meter based on ESP-12E, LTC-4150 and SSD1306 OLED module that measure the average current draw of a variable load accurately: The meter is powered by the micro-USB port on the ESP-12E. I soldered header pins onto the IN and OUT terminals of the LTC-4150. The whole idea is that […]
Open source FTDI FT2232 JTAG and UART Adapter board
Erich Styger writes: In JTAG Debugging the ESP32 with FT2232 and OpenOCD I have used a FTDI FT2232 breakout board to JTAG debug with OpenOCD. With an adapter board on top of the FTDI FT2232 the wiring is much easier and simpler to use. More details at mcuoneclipse.com
UPDI Programmer Stick
Johnson Davies designed and built this UPDI Programmer Stick based on an ATmega328P, that is available on GitHub: This is a USB-stick sized UPDI programmer, for programming Microchip’s new 0-series and 1-series ATtiny chips from the Arduino IDE It’s based on an ATmega328P, and is essentially an Arduino Uno on a USB stick, so you […]
Free PCB coupon via Facebook to 2 random commenters
Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three […]
Open source Bluetooth stack for PIC32/24
Nigan tipped us to a simple open source Bluetooth stack for embedded devices, the SmallTooth: A newly developed open source Bluetooth stack for PIC32/24 * The code is really easy to understand, very well documented and really small. * Designed to be extended and ported. * Works straight out of the box with the PIC32 […]
Single diode temperature sensor with Arduino ICU (& reverse-bias leakage)
Use a single diode as a temperature sensor with Arduino ICU Our LED light-sensing experiments lead to an interesting observation: When these loggers are left running overnight they still produce readings because reverse-bias ‘leakage-current’ eventually triggers the Interrupt Capture Unit (ICU) – in the absence of any light. The speed of this self-discharge depends on […]
#FreePCB via Twitter to 2 random RTs
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]
JesFs – Jo’s Embedded Serial File system
suchende tipped us to the small File system for NOR flash: The main problem for “very small devices” – until now – was the “File System”: everybody knows “FAT”, “NTFS”, … but have you ever thought of a file system on a small chip? Or even inside of a CPU? No problem, with the right […]
Free PCB Sunday: Pick your PCB
We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will […]
Linear Nixie tube HAT for the Raspberry Pi
Mark Smith has been working on a HAT for the Raspberry Pi that can drive two IN-9 or IN-13 linear Nixie tubes: This project as described in www.surfncircuits.com came about because I needed a retro looking linear meter for my espresso maker water tank. I’m always running out of water in my espresso maker, and […]
Cheaper yet powerful camera solutions
The Landingfield writes: It’s been a while since my last blog post. During this past year, I’ve built a few other cameras yet released on this blog. In the meantime, I have been looking into options to make this work available to fellow amateur astronomers as a viable product. One major blocker here is the […]
#FreePCB via Twitter to 2 random RTs
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]
4 Port high power USB hub
Dilshan Jayakody has published a new build: In the last couple of years, I tried several powered USB hubs to drive some development boards and USB peripherals. Most of the USB hubs which we can find in the local market are unreliable or not designed to drive more than 500mA of a load. After having […]
JTAG debugging the ESP32 with FT2232 and OpenOCD
Erich Styger has written an article on how to use an inexpensive FTDI evaluation board as JTAG debug interface to debug ESP32 based devices: In “Eclipse JTAG Debugging the ESP32 with a SEGGER J-Link” I used a SEGGER J-Link to debug an ESP32 device with JTAG. I looked at using one of the FTDI FT2232HL […]
A self-expanding ESP32 PWM board
Eric Gunnerson writes: I’ve been working on a little ESP32 expansion board/shield for an LED project I’ve been working on. One of the nice things about the ESP32 is that it has a peripheral known as “LED control” that provides 16 independent channels of PWM for controlling LED brightness, and my project uses that capability. […]
App note: Emitters and detectors for infrared (IR) touchscreens
App note from OSRAM about IR LEDs and IR detectors used on touchscreen technologies. Link here (PDF) Touchscreens as a popular user interface are more and more common. Applications span from public information systems to customer self-service terminals. Thus, as a logical step, more and more devices today feature this kind of user interface, e.g. […]