Luca made an Amp-meter using the ACS712 current sensor, and the Arduino.
The ACS712 is a fully integrated, hall effect based, linear current sensor. It converts the current that passes through its input pins to a proportional voltage on an output pin. He connected the output pin to an analog pin of his Arduino, and made a simple logging software that reads 1000 samples.
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 a every week:
You can get a Bus Blaster v2 for $34.95.
Continue reading “Free PCB coupon via Facebook to 2 random commenters”
This application note describes four methods of playing a video file using a PIC microcontroller (MCU) and hardware solutions available from Microchip. Methods discussed include video playback on PIC32 using upscaling by interpolation, streaming raw video from a micro-SD card using the SSD1926 LCD graphics controller on the Multimedia Expansion Board (MEB), streaming uncompressed AVI video over ethernet on the MEB using PIC32 and streaming uncompressed AVI video over ethernet on WVGA using PIC32sd.
After checking out Make’s mini fume extractor, Eric decided to make his own. What he had lying around was a 24v fan that couldn’t quite fit in a single Altoids box, so he soldered two boxes together to get a single wider one. Two 9V batteries connected in series provide the power for the fan, and a carbon filter keeps the bad fumes from escaping through the back.
The two boxes soldered together solution worked out well because it stands up better and won’t tip over as easily as the single Altoids box version would.
Henrik designed and built an adjustable clock source for the EasyDriver that maintains the same motor speed over a range of step resolutions. It adjusts the driving frequency depending on the resolution of steps the EasyDriver makes per input pulse.
EasyDriver is a stepper motor driver that moves the motor one preselected step for every LOW-HIGH transition it receives on it’s input pin. The direction and steeping resolution are selectable though three control pins.
Hentik’s board uses a ATtiny25 microcontroller to read the steeping resolution control pins, and adjusts the driving clock frequency, to maintain the same rotational speed. Check out a video of it below.
Ricros built a free Bus Pirate v3.5 PCB.
If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB drawer.
Get your own handy Bus Pirate for $30, including world-wide shipping. Also available from our friendly distributors.
Giovanni writes to inform us about his guide regarding the STM32F4-Discovery.
This article will explain how to get started with the recently released STM32F4-Discovery board using ChibiOS/RT. This board is really cheap (below $20) and is an excellent evaluation platform for the STMicroelectronics Hi-Performance & DSP STM32F4 family.
Via the contact form.
Luca is building a Nixie clock, and in this post he covers the high voltage power supply section.
Nixie tubes are digit displays that use ~170V between the digit wire and a wire mash, to agitate the gas inside the tube. This surrounds the digit wire with a orange glow and it becomes visible through the tube.
Luca is using the MAX1771 based DC/DC boost converter to supply the high voltage required. This DC/DC steps up the 9-12V input to 180V output, as a bonus it has an additional 5V output for the rest of the circuit board.
Raj decided to make a tutorial on how to implement a 0-99 minute timer on a PIC16F628A microcontroller. His design uses a HD44780 compatible 2×16 text LCD, to setup and display the count-down timer. One pin of the PIC should be used to drive a relay, but for testing purposes Raj used a LED instead
He utilized his DIY IO board that has a built in power supply, HD44780 LCD, 4 buttons, 4 LEDs, a buzzer, and an EEPROM. Schematic, firmware, and source code are available for this project.
The Arduino team has released the official version 1.0 of the Arduino IDE. New features include changing the file extension for sketches to “.ino”, new toolbar icons, the Serial class (as well as other classes inheriting from Stream, like EthernetClient, SoftwareSerial, Wire and more) now contains functions for parsing incoming data, support for DHCP and DNS has been added to the Ethernet library, and the SD library now supports open multiple files simultaneously. A full recitation of the updates can be found in the release notes.
Downloads are available for Linux, OSX and Windows from the Arduino software page.
Watch us solder the Bus Pirate v4.
The Bus Pirate is an open source hacker multi-tool that talks to electronic stuff. For a comprehensive overview check out our previous post.
Here are the main differences and advantages of V4 over V3:
The Bus Pirate V4 is still a work in progress. If you want a reliable and fully tested tool, we still recommend the v3. It is actively developed and will be manufactured for the foreseeable future. Development on the V4 will continue, and we will let you know when we think it is the go-to hardware.
You can get a Bus Pirate v4 for $40, including worldwide shipping.
Bus Pirate v3, and all previous Bus Pirates, are based on a chip with 64K of program space. Last year we stuffed so many features into the firmware that we used all the space. It was time for new hardware based on a new chip.
We didn’t want to run out of space again soon, so we used a PIC 24FJ256GB106 with 256K of space. More room was the main goal, but we can pull off some other fun things with the resources on the bigger chip:
Bus Pirate v4 is new and shiny, but it will lag behind the trusty v3 for a while. If you want proven goodness we still recommend the v3, it is actively developed and will be manufactured for the foreseeable future. v4 will continue to improve, and we’ll let you know when we think it is the go-to hardware.
Keep reading below for more about the new hardware.
You can get a Bus Pirate v4 for $40, including worldwide shipping. Continue reading “NEW PROTOTYPE: Bus Pirate v4”
Jdownj posted pictures of his free PICqueño PCB build. The PICqueño is our version of chipKIT’s UNO32 board. It’s a Arduino compatible device built around the PIC32 microcontroller.
If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB drawer.
Here is a USB development board for the P8X32A-Q44 Propeller microcontroller. It has a FT232RL USB-to-UART IC, a 3.3 LDO voltage regulator, a 5MHZ crystal, and a 64KB EEPROM. He broke-out 32 IO pins of the microcontroller to two 16pin female headers.
This is version 1.1 of this design, and version 2 is currently under development.
Arup built a USB Infrared Toy clone. He is working out some kinks, but we expect him to be enjoying his new toy in no time.
You can get IR Toy v2 for $22.05, including world wide shipping.
Via the forum.
Octal tipped us off about the new PIC12LF1840T48A microcontrollers that have a built in sub-GHz transmitter:
Microchip just published the datasheet related to using the PIC12LF1840T48A Microcontroller with Integrated Sub-GHz Trasmitter.
The PIC12LF1840T48A is a Microchip microcontroller that has an on-board transmitter. The transmitter is suitable for operation in the 418, 434 and 868 MHz license-free ISM bands.
Via the forum.
Christopher built an ATTiny85 development board. It has all the microcontroller pins broken out to a 2×4 dual row pinheader, a power indicator LED, and a reset button as well.
Mashiara designed an I2C controlled 4×4 RGB LED matrix. He uses 3 PCA9635 I2C-to-PWM drivers with 16 PWM outputs. Each IC controls a different basic color of the LEDs.
The up-side to this design is that all of the drivers are on-board, and only control signals are needed to manipulate the matrix. The down side is that his design requires 4 layers to route, and 4 layer boards are quite expensive to make.
Via comments.
Zipppys123 is building a DIY ultrasonic range finder based on this design. Once it’s externally triggered a PIC12C508 is used to generate generate the ultrasonic pulse, and measure its echo.
The ultrasonic pulse is amplified using a MAX232 TTL-to-RS-232 level converter, while the echo is amplified and demodulated using two op-amps and comparators.
Via the forum.
