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ถูกปรับปรุง 5 hours 32 min ก่อน

Free PCB Sunday: Pick your PCB

15 hours 51 minก่อน

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 get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Be sure to use a real e-mail in the address field so we can contact you with the coupon.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.
  • PCBs are scrap and have no value, due to limited supply it is not possible to replace a board lost in the post

Be the first to comment, subscribe to the RSS feed.

App note: Adding flexibility by using multiple footprints for I2C™ serial EEPROMs

19 hours 20 minก่อน

Save PCB space by utilizing EEPROM SOIC-8 area, here’s an application note from Microchip. Link here (PDF)

For many years, the 8-lead SOIC package has been the most popular package for serial EEPROMs, but now smaller packages are becoming more commonplace. This offers a number of benefits; the reductions in footprint size and component height are some of the more obvious ones. Smaller packages also generally offer a cost advantage over their larger counterparts.

App note: Writing to flash and EEPROM on the tinyAVR 1-series

อาทิตย์, 01/21/2018 - 20:00

Update your tinyAVR code to access memories when using 1-series tinyAVRs. Link here (PDF)

On tinyAVR® 1-series devices, access to Flash memory and EEPROM has been changed from that on previous tinyAVR devices. This means that existing code for writing to Flash and EEPROM on older devices must be modified in order to function properly on tinyAVR 1-series devices. This application note describes what has changed and how to adapt code to these changes.

STM32F103 vs GD32F103

เสาร์, 01/20/2018 - 03:47

Sjaak wrote about a Chinese ARM chip compared to a ST ARM chip:

Most of us do know the ST line of ARM chips called STM32. They come in multiple flavours and the STM32F103 is one of the most common entry level family of chips. They are called by ST as mainstream. They are a full featured 32 bit ARM Cortex M3 chip running at max. 72MHz with all the requisite peripherals like ADC, DAC, USB, CAN, I2C, I2S, SPI, SDIO, PWM, RTC, interrupts and various timers. Lets zoom into the STM32F103C8 chip (which seems the be the go-to choice of the Chinese el-cheapo development breakout boards)

See the full post at smdprutser.nl.

Free PCB coupon via Facebook to 2 random commenters

ศุกร์, 01/19/2018 - 23:26

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 times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • We’ll contact you via Facebook with a coupon code for the PCB drawer.
  • Limit one PCB per address per month, please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

TWANG, an Arduino-based dungeon crawler

ศุกร์, 01/19/2018 - 07:05

Bdring built his own Arduino-based 1D dungeon crawler inspired by Robin Baumgarten’s  Line Wobbler:

I have been a Patron of Robin Baumgarten for a while. He makes experimental hardware for games. His Line Wobbler one dimensional dungeon crawler is my favorite and I have always wanted to play it. It uses a door stop spring as the controller. An accelerometer in the knob allows it to work like a joystick and also detect the wobble used to attack the enemies.

More details at Buildlog.net blog.

Yield function, printable class and mapping arrays: Useful but unknown features from Arduino core

ศุกร์, 01/19/2018 - 05:51

Yahya Tawil over at Atadiat wrote a new tip for Arduino developers about three hidden and useful features in Arduino core:

Arduino core, the source code of Arduino API functions and classes, has three useful features that can be used effectively. As the Arduino core documentation doesn’t mention them (at least until the time of publishing this micro-blog), these features are not well-known for arduino developers. Let’s discuss each feature of them one by one.

More details at Atadiat blog.

Via the contact form.

 

IBM mainframe tube module part II: Powering up and using a 1950s key debouncer

พฤ, 01/18/2018 - 06:14

Here’s an interesting two-part series of posts by Ken Shirriff detailing the IBM mainframe tube module.

Part 1 discuss the tube modules and describe the IBM 705 that used this module. Part 2 covers powering up the module and getting it to work.

Read the full post at Ken Shirriff’ blog.

A journey into Capcom’s CPS2 silicon – Part 2

พุธ, 01/17/2018 - 05:46

Here’s an informative part 2 of the Capcom CPS2 reverse engineering series by Eduardo Cruz:

Capcom’s Play System 2, also known as CPS2, was a new arcade platform introduced in 1993 and a firm call on bootlegging. Featuring similar but improved specs to its predecessor CPS1, the system introduced a new security architecture that gave Capcom for the first time a piracy-free platform. A fact that remained true for its main commercial lifespan and that even prevented projects like Mame from gaining proper emulation of the system for years.

See the full post on the Arcade Hacker blog. Be sure to see Part 1 here.

#FreePCB via Twitter to 2 random RTs

พุธ, 01/17/2018 - 04:21

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 it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter with a coupon code for the PCB drawer.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

Programming STM32F103 Blue Pill using USB bootloader and PlatformIO

อังคาร, 01/16/2018 - 06:10

Coyt Barringer wrote a post on his blog showing how he program the Blue Pill STM32F103 using USB Bootloader and PlatformIO:

This is the infamous Blue Pill board – a $2 ARM STM32F103 development board with all the capabilities of a Teensy 3.x at a fraction of the price of an Arduino. So what’s the catch?
I’ll tell you – software support.
A couple weeks ago I decided to invest some time learning this platform because I was sick of paying 20+ dollars for a Teensy. While the PJRC platforms are fantastic, they are expensive and need a proprietary boot loader in order to work. I want a small and powerful arm chip which I can integrate INTO my own PCBs and the Teensy does not easily or cheaply allow this. The Blue Pill and it’s derivatives appear to be just the thing I need!

See the full post at lostengineer.com.

Arduino Tutorial: Adding sensors to your data logger

อังคาร, 01/16/2018 - 05:43

Edward Mallon writes:

This post isn’t another How-To tutorial for a specific sensor because the Arduino community has already produced a considerable number of resources like that.  You’d be hard pressed to find any sensor in the DIY market that doesn’t give you a dozen cookbook recipes to follow after a simple Google search. In fact, you get so many results from “How to use SensorX with Arduino” that beginners are overwhelmed because few of those tutorials help people decide which type of sensor suits their skill level. This post attempts to put the range of different options you can use with a Cave Pearl data logger into a conceptual framework, with links to examples that illustrate the ideas in text.

More details at thecavepearlproject.org.

Inside a PM1A color analyzer

อังคาร, 01/16/2018 - 05:12

Kerry Wong did a teardown of a PM1A color analyzer:

As I mentioned in one of my posts a few years back, a color analyzer from the 80’s can be a treasure trove for the hobbyists. And at the very least, it is a cheap way to get yourself a photomultiplier along with the supporting circuitry to do experiments with. For instance, you can utilize the fast response time of a PMT to do accurate speed of light measurement in a lab setting like I showed in this experiment back in 2015.
I just bought another one off eBay, and this time it is a Beseler PM1A color analyzer. By the look of it, it is probably a cheaper version of the Beseler PM2L I did a teardown and reverse engineering with before.

See the full post on his blog.

Check out the video after the break.

Free PCB Sunday: Pick your PCB

จันทร์, 01/15/2018 - 04:58

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 get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Be sure to use a real e-mail in the address field so we can contact you with the coupon.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.
  • PCBs are scrap and have no value, due to limited supply it is not possible to replace a board lost in the post

Be the first to comment, subscribe to the RSS feed.

App note: PWM Basics

จันทร์, 01/15/2018 - 00:00

PWM basics and PWM drivers app note from APEX Microtechnology. Link here (PDF)

PWM circuits are taking the same general course of development traveled by op amps and many other electronic functions. Concepts were brought to life using discrete components and were followed by modules, hybrids and then monolithics.

App note: Microphone specifications explained

อาทิตย์, 01/14/2018 - 20:00

All about MEMS microphone from TDK Invensense. Link here (PDF)

A MEMS microphone IC is unique among InvenSense, Inc., products in that its input is an acoustic pressure wave. For this reason, some specifications included in the data sheets for these parts may not be familiar, or familiar specifications may be applied in unfamiliar ways. This application note explains the specifications and terms found in MEMS microphone data sheets so that the microphone can be appropriately designed into a system.

Free PCB coupon via Facebook to 2 random commenters

เสาร์, 01/13/2018 - 05:25

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 times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • We’ll contact you via Facebook with a coupon code for the PCB drawer.
  • Limit one PCB per address per month, please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

FPGA-based disk controller for Apple II

เสาร์, 01/13/2018 - 04:55

Steve Chamberlin over at Big Mess o’Wires has been working on an FPGA-based disk controller for Apple II, which he call Yellowstone:

Apple II disk controller cards are weird, there are a crazy number of different types, and many are rare and expensive. Can an FPGA-based solution save the day for retro collectors? You bet! Nearly all the existing disk controllers connect the same 8-bit bus to the same 19-pin disk interface, so a universal clone is merely a question of replacing the vintage 80s guts of the card with a modern reprogrammable FPGA. This hypothetical universal controller card could connect to almost any Apple II disk drive, or a Floppy Emu. Here’s my first attempt.

More details at Big Mess o’ Wires homepage.

ESP32lights

ศุกร์, 01/12/2018 - 06:48

Luca Dentella published a new build:

Today’s project, ESP32lights, is a smart device based on the esp32 chip.
Thanks to ESP32lights you can turn a load on and off (I used it for my christmas lights)

  • manually
  • based on daily schedules
  • based on the light intensity

ESP32lights connects to your wifi network, can be configured and operated via a web browser and it’s optimized for mobile devices (responsive web interface based on jQuery Mobile).

Full description on his blog. More tutorials about the ESP32 chip here.

Check out the video after the break.

Common emitter amplifier design tips & shortcuts

พุธ, 01/10/2018 - 21:04

Tips & tricks for the common emitter amplifier design by Alan Wolke (aka W2AEW)

This video provides some basic design tips and shortcuts for the Common Emitter, Class A, Amplifier. The considerations for selection of the DC Bias point are presented, as well as some tips on how to set/compute the gain for both degenerated and high-gain configurations.