An open-source USB to CAN adapter: It supports CAN bit-rates of up to 1 Mbit/s. The product comes with an open-source SocketCAN driver software. It features a Micro-USB connector and a 4-pin screw terminal with CAN_H, CAN_L, 5-V supply, and ground. The CANable device is a hardware clone of Eric Evenchick’s CANtact project, an open-source […]
Author Archives: DP
Arduino time attendance system with RFID
A how-to on building a time attendance system with MFRC522 RFID Reader and Arduino from Random Nerd Tutorials: Before getting started it’s important to layout the project main features: *It contains an RFID reader that reads RFID tags; *Our setup has a real time clock module to keep track of time; *When the RFID reader reads an […]
#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 […]
Microsoft “Intellimouse” teardown
Microsoft “Intellimouse” teardown from Electronupdate: Before the advent of optical mice, the go to technology was a steel ball which moved two drive shafts to indicate position. A good example of this is this Microsoft “Intellimouse”. As expected the electronics are built around a small micro controller Check out the video after the break.
Raspberry Pi GPIO programming in C
Steve Chamberlin has written an article about Raspberry Pi GPIO programming in C: The Raspberry Pi’s 40-pin GPIO connector often gets overlooked. Typical Pi projects use the hardware as a very small desktop PC (RetroPie, Pi-hole, media center, print server, etc), and don’t make any use of general-purpose IO pins. That’s too bad, because with a […]
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 […]
App note: How to properly configure unused operational amplifiers
Good read app note from Texas Instruments about configuring unused op amps on multi amp chips. Link here (PDF) Multi-channel operational amplifiers (op amps) are often implemented in circuits that do not require the use of all channels. Undesired behavior in an unused amplifier channel can negatively impact system performance, as well as the performance […]
App note: Current sense amplifiers in class-D audio subsystems
App note from Texas Instruments about output current sensing in class-D amplfiers. Link here (PDF) Current sensing in audio subsystems are widely used in conjunction with CLASS-D amplifiers for diagnostics or to provide speaker current feedback to the DSP for speaker enhancement to emulate smartamp. The most expensive component in the audio subsystem is the […]
Adding the Nokia 5110 LCD to your Arduino data logger
From the comments on our ChipKIT based weather station using BME280 sensor module post, Edward Mallon writes: A lot of us have ended up at this sensor / screen combination. But I couldn’t afford the extravagance of six dedicated control lines on our little pro mini based loggers. However with some slight modification, you can drive […]
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 […]
Inside the 76477 space invaders sound effect chip: Digital logic implemented with I2L
Ken Shirriff has written an excellent in-depth look at the 76477 sound effects chip: The 76477 Complex Sound Generation chip (1978) provided sound effects for Space Invaders1 and many other video games. It was also a popular hobbyist chip, easy to experiment with and available at Radio Shack. I reverse-engineered the chip from die photos […]
Banana Pi DLNA media server
Dilshan Jayakody published a new build: Couple of months back we decided to create our own media server to store our MP3s and digital photographs. But it gets postpone several months due to unavailability of main-boards and other resources. Finally, after reviewing several prototypes we decided to build our media server using Banana Pi (BPI) […]
SI5351 VFO project
Dave Richards (a.k.a. AA7EE) has a nice write-up about building another Si5351 VFO project: To many, this will be just another Si5351 VFO project, with nothing to distinguish it from the others. In fact, that’s exactly what it is. The “how to” of connecting an Arduino board to an Si5351 board, wiring up a display, […]
#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 […]
Teardown of a GM3120 electromagnetic radiation tester
Kerry Wong did a teardown of a cheap GM3120 field strength meter: There are a lot of cheap electromagnetic radiation testers out there which boast some quite impressive claims. So I decided to pick up a popular one (GM3120) from eBay to see how well it works. And perhaps more importantly, I wanted to take […]
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 […]
App note: Pulsed Over-Current Driving of LEDs
App note from CREE on driving LEDs over its specified current capability. Link here (PDF) The Applications Engineering team at Cree is often asked whether it is safe to operate Cree XLamp® LEDs with pulsed currents above the maximum data-sheet rating. This question is usually asked in the context of legitimate product requirements such as […]
App note: Optimizing PCB Thermal Performance for LEDs
Application note from CREE on efficiently designing a conventional FR4 PCB to manage thermal heat and as a cheap alternative to metal core pcbs. Link here (PDF) One of the most critical design parameters for an LED illumination system is the system’s ability to draw heat away from the LED junction. High operating temperatures at […]
Rombus pinball – a LattePanda mini pinball machine
Matt Brailsford (aka Circuitbeard) has a nice write-up about building his mini pinball machine with a lattepanda core running dual monitors: I generally start my projects by thinking about the hardware that I’m going to want to use as I’ll need to know sizes when it comes to the design phase. My first thought was to […]
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 […]