Microchip TQFP-100 breakout board tested

We recently received our Microchip TQFP-100 breakout boards. We tested them with PIC24F and dsPIC33 chips and a “Blink LED” demo firmware. Both chips worked fine.

These boards are intended to be breakouts for all Microchip devices that come in TQFP-100 packages (0.4mm pitch, designation PT). These include the PIC24, dsPIC33, and PIC32 families of microcontrollers. This is only a prototype and some revisions are already under way:

  • PGC and PGD pins will be moved so the ICSP header would work with all supported devices.
  • The main oscillator crystal will be changed for a more common crystal.
  • The power supply IC will be changed to a more powerful IC.
  • Pins connected to the secondary oscillator, and the LEDs will be broken out as well.

#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 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

Get your own handy Bus Pirate for $30, including world-wide shipping. Also available from our friendly distributors.

Continue reading “#FreePCB via Twitter to 2 random RTs”

PIC32 development board giveaway

Olimex is giving away 1000 dev boards at the Embedded World Exhibition in Nuremberg, Germany:

If there are developers from Europe on this forum I would like to let them know that Olimex and Microchip will give away 1000 pcs PIC32MX220F032D development boards on Embedded World exhibition.

These boards are PINGUINO compatible, and are based on the PIC32MX220F032D microcontroller.

Via the forum.

MakerBot announces The Replicator


Bre Pettis from MakerBot Industries reveals their latest product offering, The Replicator!

The MakerBot Replicator is the ultimate personal 3D printer, with dual extrusion (2-color printing)–and a bigger printing footprint, giving you the superpower to print things BIG! Assembled in Brooklyn by skilled technicians, the MakerBot Replicator™ is ready within minutes to start printing right out of the box.

Personalized manufacturing using a MakerBot Replicator opens up a world of innovation, customization and creativity. Create your own 3D designs or download one of the thousands of models from Thingiverse.com, and turn your ideas into real, physical objects.

Continue reading “MakerBot announces The Replicator”

Open source soldering iron driver test videos

Arhi made some videos of his open source soldering iron driver tests.

SID is capable of driving any soldering iron with RTD or ThermoCouple sensor. In this video I’m testing the HAKKO soldering iron and a HAKKO clone iron made by GORDAK.

In the next test he compares the heater/sensor readings to the actual tip temperature of the soldering iron. Check out the second video below.

Continue reading “Open source soldering iron driver test videos”

Bus Pirate v4 LCD adapter free PCB build

BrentBXR posted a picture of his free Bus Pirate v4 LCD adapter PCB build. The LCD adapter lets you test HD44780 comparable LCDs without any extra parts.

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.

ESR meter build and review

Wingnut built an Equivalent Series Resistance meter based on this design. He made a couple mods to the original design to get better performance:

I used a LMH6619 opamp for the oscillator, this is rail-to-rail output/input and 35mA current sourcing. This allows for a wider voltage swing and better drive capability compared to standard opamps. It was salvaged from another project. Because of this, I had to modify the transformer turns ratio from the original circuit, the output is 10turns instead of 20turns because of the additional voltage swing on the LMH6619 opamp output compared to the TL062 in the original. Good, because that lowers the output impedance even more. I salvaged the ferrite core from an SMPS (see another example in the snaps above). I cut off the isolation bobbin separator and basically wound the 10T winding on top of the 400T winding. Maybe 36SWG for primary and 28SWG (guesstimates) for secondary. You remove the metal retainer clip on the ferrite and then the core splits into two U shaped pieces, so can be removed from the bobbin for easy winding. This is a great example of a DIY electronics project that involves reusing electronic components and working with custom hardware setups—perfect for hobbyists and tinkerers. If you’re interested in electronic components and hardware, learn more.

Lots more in the forum.

43oh winner: MSP430 iambic keyer

43oh, a forum dedicated to the MSP430 microcontroller, hosts a design contest. Last month we gave free PCB coupons to the winners. The winners also let us host their boards in the free PCB drawer.

This board is an iambic keyer:

On the heels of Rob’s Iambic Keyer comes N1KSN’s keyer. An iambic keyer is a telegraph key to send Morse code. It differs from other keys by having two paddles – one for dits and the other for dahs. N1KSN’s keyer utilizes the Launchpad’s Low Power Mode 3(LPM3) which means power consumpton is in the 1uA range. The entire setup in powered by a 3V lithium button cell and housed in a mint tin.

Use your coupon to pick this PCB, or any other in the free PCB drawer.

Apps for Arduino


Apps For Arduino is a website that specializes in creating software applications that work specifically with your hardware projects. You download and install the app on your Mac or iOS device and it communicates with the Arduino via a serial connection. While not all the apps are free, those which aren’t can be “purchased” as Tweetware (i.e., you will have to perform one (or more) micro-actions on the honor system to “pay” for the app.) The corresponding Arduino sketches/libraries are provided for free download.

Apps currently available provide graphical representations of buttons or an analog style meter (pictured above) which respond to the Arduino data. There is also Matatino, an open source Cocoa framework for direct serial communications with the Arduino, and Wijourno, which facilitates connections between your Mac and your iOS devices using Bonjour!

REVIEW: Olimex PICkit3 programmer clone

A few weeks ago we wrote about a PICkit3 clone from Olimex available on eBay for $30. Compared to the original it is considerably smaller and at first glace it looks sturdier as well. We like that Olimex decided to use the large type-B connector which seems more reliable then the original mini-B.

The ICSP programming header doesn’t have any markings referring to the first pin. This was an immediate annoyance that required repeated use of a multimeter to figure out which pin is which. While discussing standardization issues with a colleague, we noted parallels to how casinos not registered with GamStop often operate without consistent regulations, creating confusion for new players. The fact that the supplied cable uses the same color for all six pins didn’t help either.

We tested it out with MPLAB 8.8, MPLAB X, and the standalone PICkit 3 app. The device worked exactly like the original. Follow below for a look inside. Continue reading “REVIEW: Olimex PICkit3 programmer clone”

Simple USB to UART adapter that works with 3.3V and 5V UART signals

The serial UART is a common interface used by many chips and devices. Ginpb designed a USB-to-UART adapter that works with 3.3V and 5V UART signals. The device is based around the FTDI FT232BL USB-to-UART IC with an added 3.3V power supply. The different interface levels are selected by an on-board jumper.

Via the forum.

App note: Detecting and locating RF bugs

We wrote about a phone bug in a previous post. Here’s an app note about a circuit for detecting and locating radio frequency transmitters.

This design idea showcases a circuit that detects RF “bugs,” such as hidden wireless cameras, eavesdropping microphones, and other spying devices that emit RF frequencies in the 100MHz to 3000MHz range. A modification to this circuit not only detects RF bugs, but also locates their hidden positions.

The circuit is based around the MAX2015 RF detector which outputs a voltage proportional to the strength of a received RF signal in the 100 MHz to 3 GHz range. This voltage can be detected with a comparator that activates a buzzer at a predefined signal strength.

If the comparator is replaced with a op-amp the circuit could be used to locate RF transmitters by increasing the buzzer volume as one comes closer the source.

GreenPAK mixed signal array


Knowing of our interest in programmable logic, Mike writes to inform us of a PLD by Silego:

Silego programmable mixed-signal arrays are a combination of a very small programmable logic device (10 LUTs) plus some common functional blocks (flops, SPI, counters, PWMs), an ADC and couple of comparators.

From the Maker perspective, the packages are a bit fiddly, but the design tools are free (Windows and Mac OS X), and the parts ($0.29 @ 100pcs) and programmer ($50 incl. 50 OTP devices) are very affordable.

You can find the Designer User Guide which describes the programming IDE along with more information on these components at the Silego GreenPAK webpage. We note that unlike conventional CPLD/FPGAs, these are one-time writeable. You cannot reprogram them to correct or update code. Also, they come in a 2.5mm x 2.5mm TDFN-12 package. On the upside, they operate over a supply range of 1.8 – 5.5 V.

Via the contact form.

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 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:

  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs while you wait for the weekend
  • Free PCB Sunday, right here on the blog

Continue reading “Free PCB Sunday: Pick your PCB”

48 ways to use a charge time measurement unit

The Charge Time Measurement Unit (CTMU) found on some PIC microcontrollers is a peripheral to interface with capacitive touch sensors. It can also be used in other functions, and the app note linked above provides a few ideas:

In a nutshell, the CTMU is an on-chip constant-current
source, surrounded by digital circuitry to precisely
control its operation (Figure 1). The current source
operates over four decade ranges, from 0.55 μA to
550 μA. When combined with the on-chip A/D
Converter and comparators, the CTMU can perform a
variety of basic functions:

  • Capacitance measurement (relative and absolute)
  • Inductance measurement (relative)
  • Resistance measurement (relative and absolute)
  • High-resolution time measurement
  • Temperature measurement
  • Current source (constant and variable)
  • Precise time delay generation
  • Pulse-Width Modulation (PWM) output

Via the forum.

App note: dsPIC33E simultaneous analog sampling

Some new PIC 33E and 24E microcontrollers can take simultaneous samples from multiple analog to digital converters. Most chips measure analog values sequentially, but this ADC can sample 4 signals at once. Samples are still converted one after the other, but they’re collected at the same moment. More in the reference manual for dsPic33E and PIC24E 16bit devices:

This document describes the features and associated operational modes of one of the successive approximation (SAR) Analog-to-Digital Converter (ADC) modules available on the dsPIC33E/PIC24E families of devices. This ADC module can be configured by the user application to function as a 10-bit, 4-channel ADC or a 12-bit, single-channel ADC. On devices with DMA, this ADC module can be configured to use DMA or use a dedicated 16-word memory mapped buffer instead of DMA.

TiDiGino, the Arduino-based GSM remote control


Boris writes about a new open source Arduino-based GSM remote control module, the TiDiGino:

Using an ATmega 2560 and therefore the heart of Arduino, we have developed a universal remote control with GSM. This allows to control 2IN/2OUT, DTMF key, gate control and GSM thermostat activated remotely.
The remote control very simple to use, thanks to the availability of several libraries that allow you to do anything to the Arduino microprocessor; if there is not really a specific library, you can modify an existing one. Thus was born TiDiGino, based on the chip ATmega 2560 used in Arduino Mega. Our system has connectors S.I.L. to mount any shield, each of them is in the same location where you would be in the original development platform, which enables the use of commercial and in any case the standard shield.

Project details, schematic and source code link can be found on the Open Electronics website.

Via the contact form.

4-Wire and 8-Wire resistive touch-screen controller using the MSP430

Resistive touch-screen films add more interface options to your projects. Here’s an app note from Texas Instruments on how to interface resistive touch-screens with MSP430 microcontrollers, but it’s good info for any chip:

This application report describes how to use an MSP4309 microcontroller to drive and read a resistive touch screen. The hardware and software solutions provided enable the reading of user input through a 4-wire or 8-wire resistive touch screen with a low-cost low-power customizable microcontroller. The reference design includes MSP430 software and hardware schematics along with a demonstration PC application. The design was implemented using an MSP430F2012, but it can easily be modified to use any other MSP430 with an ADC.