App note: Long Delay Generation Using the AVR Microcontroller

long_delay_gen_AVR

Here’s an app note from ATMEL presenting a solution for microcontroller long delays.

The solution presented here shows how the AVR AT90 series microcontrollers (AT90S2313, AT90S4414 and AT90S8515) generate and handle long delays. On-chip timers are used without any software intervention, thus allowing the core to be in a low-power mode during the delay. Since the timers are clocked by the system clock, there is no need of any additional components.
Due to the very long timing capability, this implementation combines high system performance with long delay generation. For example, an AVR Microcontroller running at
20 Mips can generate delays as long as half an hour.

App note: Capacitive Multibutton Configurations

capacitive_multitouch_config

A capacitive mutibutton configuration application note from Microchip describing how to scan and detect button presses on more than 4 capacitive buttons.

This application note will discuss three different
approaches to implementing multiple touch buttons
using Microchip microcontrollers. The first approach
creates a simple 4 sensor system using the on-chip
4-to-1 analog multiplexers tied to the inputs of the
comparator module. The second approach expands
the 4 sensor system of the first approach, into a 10
sensor system by combining pairs of the original 4
inputs. The third approach creates an expandable
system, which relies on multiplexing additional
sensors through an external analog multiplexer.

FreeMat: another MATLAB replacement


MATLAB is software tool providing a high-level language and interactive environment for numerical computation, visualization, and programming. It is not open source and has a costly licensing structure making it impractical for the casual experimenter.

There are free open source alternatives, one of which is FreeMat. “FreeMat is an interpreted matrix-oriented development environment for engineering and scientific applications, similar to the commercial package MATLAB. FreeMat provides visualization, image manipulation, and plotting as well as parallel programming.”

FreeMat tutorials can be found on Google code, with additional information and code downloads for Linux, Mac OSX and Windows available on the FreeMat Sourceforge page.

Via Linux Journal.

MCC8 – PIC24 based CHIP-8 game emulator

BootScreen

Here’s another project by Mats the handheld PIC24-based CHIP-8 emulator game console:

This is a small handheld PIC24-based CHIP-8 카지노사이트 emulator game console. A cheap Noika 1202 LCD is used as the display and a CR123A 3 volt lithium battery for power.

CHIP-8 is an interpreted programming language, developed by Joseph Weisbecker. It was initially used on the COSMAC VIP and Telmac 1800 8-bit microcomputers in the mid-1970s. CHIP-8 programs are run on a CHIP-8 virtual machine. It was made to allow video games to be more easily programmed for said computers.

You can find the project details on github.

Via the project log forum.

Free PCB coupon via Facebook to 2 random commenters

Dp-qfp-proto-v2

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. More PCBs via Twitter on Tuesday and the blog every Sunday.

Don’t forget there’s free PCBs three times every week:

Continue reading “Free PCB coupon via Facebook to 2 random commenters”

Week in (p)review November 22, 2013

Exercise12_W600

Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon.

Coming up:

  • Free PCBs via Facebook on Friday
  • App notes on the weekend
  • Free PCB Sunday
  • Free PCBs via Twitter on Tuesday
  • Weekly roundup and preview every Friday

A PIC16F145x based PIC16F145x USB programmer

2013-11-22_1254

From the comments on our PIC16F145X: Full-Speed USB with no external crystal post, Maurice Bos writes:

I wrote software to turn a PIC16F145x into a PIC16F145x programmer (over USB). It’s free and open source (GPL3), and it might be useful.
Add any feature requests (or bugs) on Github, or just e-mail me. :)

Via the comments.

Secure Drop open source project

securedrop_logo
“SecureDrop is an open-source whistleblower submission system managed by Freedom of the Press Foundation that media organizations use to securely accept documents from anonymous sources. It was originally coded by the late Aaron Swartz.”

SecureDrop is dependent on the Tor project, meaning sources who submit documents and journalists who download these documents must connect to the SecureDrop website using the Tor network.

For more information on this project visit PressFreedomFoundation. Code can be found on GitHub.

Building a self balancing bot

self-balancing-bot-1

Bajdi documented his Arduino self balancing bot build:

For the electronics I used one of my own PCB creations, a Bajduino of course :) It’s just a small (50x50mm) break out board for an ATmega328. I’m running the ATmega @ 16MHz and 3.3V. It’s out of spec according to the datasheet but it works… I also needed an IMU of course. I found a MP6050 sensor in my parts box. The MPU6050 combines a 3 DOF gyro and 3 DOF accelerometer in a small package, ideal for a self balancing bot.

Business Card version 2

thumb_bcv2_front

Brian posted an article describing how he designed and built his business card:

A business card should represent a person’s expertise. My expertise is in creating unique circuit boards, so to celebrate this I wanted to create a USB thumb drive circuit that contains my resume and contact information. This was also a great way to experience coding for USB applications using the Cortex M series of microcontrollers. As a side note, I have done other projects with Cortex M including a simple serial relay and a USB keyboard emulator, but this is the first one that is exciting enough to write about.

Mini button breakout board

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Kevin Rye writes:

I came up with the idea that it would be cool to have a little button breakout board that I could quickly pop on to my breadboard when I suddenly found myself in need of some buttons. Instead of scrounging for buttons and resistors and taking up a whole ton of space, I could just simply connect a “mini keyboard” to the breadboard and be up and running in seconds.

Via the contact form.

Sick Of Beige Basic Case v1 (DP7043) back in stock

basic case v1P7043

Sick Of Beige basic case v1 (DP7043) is back in stock at Seeed Studio.  A clear laser-cut acrylic project case kit that fits DP7043 golden-rectangle PCBs (70mmx43mm). Protect your project from electrical shorts and fingers, but keep it accessible for hacking and showing off.

Sick Of Beige Basic Case v1 (DP7043) for $3.

Arduino Astronomical clock for automatic light control

insideW

Here’s a project log covering the build of  an Arduino Astronomical clock for automatic light control by Paulo Oliveira:

My objective with this project was to build a system that, given my latitude and longitude coordinates and the current time/day of the year, automatically calculates the sunrise and sunset times, controlling the lights accordingly. There are of course commercial products that do this (see this one from Amazon for example), but it is so much more fun to build one:)

microTone Module – Simple Analog hardware interface

utm-pic16f628a

Here’s an open source project the microTone Module by Dilshan Jayakody:

microTone Module is analog interface to connect microcontrollers or digital logic systems with PCs. This interface use PC sound card’s audio output terminal to send commands to external hardware systems.

Project’s software source codes and hardware designs are available to download at sourceforge.net.

STM32F4Stamp, a breakout board for STM32F4

stm32f4stamp_fitsintobreadboard

Frank Zhao posted his STM32F4 breakout board in the project log forum:

I really like the STM32 family of ARM microcontrollers. This breakout board is a narrow design that fits perfectly on a breadboard. Every pin is accessible. It has USB, a reset button, and a bootload button. The chip itself has a permanent USB bootloader that is activated by the bootload button. This means that no equipment is required to program this microcontroller, no expensive debugger, nothing at all except a USB cable.
Design files are open source and can be downloaded, there is also a short video about the bootloader and more instructions

I am also giving away blank PCBs to those interested (see “giveaway” on my page), Seeed makes more than I need, every single time

Via the forum.

Reflow toaster oven using an Arduino


Ray Wang writes, “Hi, I recently built a reflow toaster oven using an Arduino. I know it’s pretty standard stuff, but my version has an automatic oven door opener (using a servo) and circulation fan to speed up the cooling time, and remote notification using an RF transmitter.”

You can find the project details on the blog at RaysHobby.

Via the contact form.

uCAN – protocol stack for microcontroller networking update

IMG_20131118_191554

Nick Johnson over at Arachnid Labs posted an update on his uCAN- a protocol stack for microcontroller networking we posted previously:

First working uCAN hardware! It’s not much to look at, but it is fully functional! A power injector with a 12v wall wart, a Raspberry Pi with uCAN expansion board, and an Arduino Uno with uCAN shield, connected together into the first fully functional uCAN network – at hardware level, at least. :)
A simple Arduino program sends incrementing 4 byte packets at 100 kilobits

Via the forum.

R-Pi and RTL-SDR = AFSK transmission between two Linux boxes


This video depicts the successful transmission of AFSK data via a radio link between two Linux machines using a R-Pi and an RTL-SDR dongle. The crew at Kprod posted this cool RTL-SDR project on their blog. They use minimodem to do the encoding in a FLAC or in a WAV format, then use the R-Pi as a transmitter. The RTL-SDR is setup to receive the signal and send the audio to minimodem for decoding.

#FreePCB via Twitter to 2 random RTs

xQFP80-+65-Protoboard-W800-600x474

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.

LPC812 Breakout board

LPC812_top

cpldcpu writes:

I grew fond of NXPs new LPC800 Cortex M0+ microcontrollers. I designed a small breakout for the LPC812 TSSOP20. This is the second revision. It includes push buttons for reset and activating the serial bootloader. The board has an integrated 500mA 3.3V LDO to supply both the MCU and connected devices from the USB port.

The four pins on the top side (5V,RX,TX,GND) can be used to connect a cheap USB to serial adapter and program the device via the internal bootloader using FlashMagic.

Via the project log forum.