Wednesday, September 30, 2015

Blast from the Past: Tandy 1000TL/2

A little over two years ago I was finishing building the XTIDE Adapter with the Dangerous Prototypes free PCB. Using their Bus Pirate I was able to flash the CPULD, but you need a computer to flash the BIOS. Upon pulling my Tandy 1000TL/2 (my first computer were I learned the basis of everything I do today) out of the closet, I realized after trying a standard keyboard that it requires an XT keyboard. Drat! When my wife and I moved first moved to Monterey, I had gotten rid of a bunch of stuff. I couldn't remember if the Tandy keyboard was one of them. I know I got rid of the monitor(s) and dot matrix printer. Either way, I still haven't found it.

Once in a while I would think about this project and looked up ways to create an adapter from AT to XT. It's cheaper and it takes up less space then getting a $$$ XT clicky keyboard on eBay. More recently I had found some decently priced ones on eBay but never pulled the trigger. 

Then after our trip to the Portland Mini Maker Faire and staying/talking to my best friend, it sparked my motivation to finish this project. We had visited a computer recycling place in search of a keyboard. They thought they had one, but not all 5pin din keyboards from yesteryear are XT. So looking on eBay can be tough as well. The best bet are ones that obviously have a switch.

Sunday, August 9, 2015

VA Tester and our Giant Star

Once upon a time on a bright and sunny afternoon, I decided to interact with some photons from that big burst of energy we revolve around. I had ordered a 6V 3.5W solar panel from Amazon awhile back but I never got around to trying it. I also had an Adafruit Solar LiPo Charger that I hadn't used.  Part of this is research of using solar with home automation nodes that are near a window. Currently, I use AA batteries but I see them as wasteful since eventually you have to replace them. Of course you can get rechargeable AA batteries but they usually put out a tad less voltage, 1.2V vs 1.5V and still uses energy from an outlet to recharge. ( could recharge them from solar?) This setup using off the shelf parts is a bit more pricey but in theory could last indefinitely on the same set of batteries. The Adafruit charger is where the magic happens. It takes care of load sharing with a 1S LiPo battery when there isn't enough Sun and it will charge when there is enough Sun. Ideally in the end, I would design a node that incorporates this circuit but it's really only needed for window nodes.  I could create two types of nodes - one for solar and one without, or an easy add-on board to solar enable a node, hmm...

Tuesday, July 21, 2015

The Proto Buildbar

This summer, we had the pleasure of attending a beautiful wedding near Dayton, Ohio. Since many of MobileWill's family members were also there, we decided to prolong our visit to about a week. One of the things we always like to do before visiting an area is to look up local eateries, coffee shops, museums, and such. A few places stuck out (which is always a plus, especially in the mid-west!), specifically the National Museum of the United States Air Force and a couple of new dining experiences. Yes, we've been dreaming about biscuits from Bob Evans. But we must admit, besides those things and just spending time with family, there wasn't much else to do. That is, until MobileWill's cousin recommended perhaps one of the coolest places in all of Ohio...

The Proto Buildbar.

Sunday, July 5, 2015

Arduino Zero Has Arrived!

The long awaited Arduino Zero has arrived! This is the version from CC not SRL. Looks like some retailers such as Adafruit has/had the SRL version already. Wonder if they will switch, perhaps since they began manufacturing for Arduino in the U.S.? Shipping via USPS with regular mail was painstakingly slow, especially since they are rolling out phase two of their plan. It arrived five days later than scheduled, but alas, that is my error for not choosing USPS priority mail. I could go on and on about their delivery times and dealings, but it would mean writing another post about it. 

Anyway, now that rant is out of the way, I can rant about the poor packaging. This is my first order directly from the Arduino U.S. store, so I had no prior expectations. What I received was a standard manilla padded envelope with the familiar Arduino box inside. Upon removing the small box, it had been noticeably smashed at least once. I immediately checked to see if the headers were damaged. Thankfully the Zero was fine. However, the lack of protected packaging could have easily made that a different story. The box they use isn't crushed-proof, I believe it is just their standard retail packaging. To top it off, the Zero inside has zero antistatic protection. None, whatsoever. I was in a bit of shock, especially since is well known. It would cost them less than pennies to at least outfit the Zero with a antistatic bag. Actually, come to think of it, all of their products should be in antistatic bags, in my opinion. (If you've seen this from Dave Jones' EEVblog, then you know what I'm talking about!)

Not all is lost, though! Now down to the good stuff bout what was inside the small box: the Arduino Zero. It is the first Arduino with the Atmel Embedded Debugger (EDBG). Here is a video with a good overview of using the EDBG with the Zero.  This is like the Arduino Due in price and that it gives you a 32bit ARM microcontroller, however, not quite as large - it's much smaller like the UNO and it has the Atmel Embedded Debugger.

Arduino Zero and Packaging
Mine arrived as pictured. One thing to note is the JTAG headers for the Embedded Debugger/serial link is populated but the SWD interface for connecting another target board is not. If you need it you will need to get the smaller 1.27mm headers. Looks like there is an adapter kit on Amazon.

Differences vs other Arduino's

  • 32-bit core that allows operations on 4 byte wide data within a single CPU clock. (For more information see the int type page).
  • CPU Clock at 48MHz
  • 12 channels DMA controller that can relieve the CPU from doing memory intensive tasks
  • 32 bit Real Time Counter (RTC) with clock/calendar function.
  • 32 bit CRC generator
  • Two-channel Inter IC Sound (I2S) interface
  • Peripheral Touch Controller (PTC)


MicrocontrollerATSAMD21G18, 32-Bit ARM Cortex M0+
Operating Voltage3.3V
General purpose I/O Pins20, all of which can do digital I/O and all except for 2 and 7 can be used as PWM output
Analog Input Pins6, 12-bit ADC channels
Analog Output Pins1, 10-bit DAC
External InterruptsAvailable on all pins except pin 4
DC Current per I/O Pin7 mA
Flash Memory256 KB
EEPROMNone (part of the Flash memory may be used as a non-volatile storage with some limitations*)
Clock Speed48 MHz

*Copied from

These are some very nice features that I am looking forward to trying out. Before we get to playing, we have too see how much power this thing uses. The Arduino UNO can be setup to consume very little power. Let us find out what the extra processing power will cost us...

Tuesday, June 23, 2015

STM32 Nucleo and DFU USB Bootloading

Over the last few months I have been playing with the Nucleo development boards from STMicroelectronics. If you're unfamiliar with them, they are fast, mbed and Arduino (headers) compatible. This makes it easy like an Arduino to program and use. What sets them apart is that they are 32bit and have, depending on the model, tons of memory and flash. The Nucleo boards maintain the Arduino footprint but also have headers for the extra pins which gives this board plenty of GPIO for your projects.  In turn, you end up with multiple buses such as SPI, I2C, and UARTs for your consumption. They are priced very well and come in different flavors based on your needs. Each flavor is based on different ARM Cortex architectures such as M0, M3, and M4. One of the best features is real debugging via ST-Link/V2-1. The unfortunate thing due to the nature of mbed, you can only use the debugging features using a full desktop IDE such as Keil or some of the other free alternatives. But mbed allows you to export your code from the online IDE to the project format for those IDE's. So there's that.

Most of my projects spend very little time on the development board. Once they are working, I usually want to design a PCB for it. Therefore I prefer to use microcontrollers that support native USB programming, such as the popular ATMega32U4. With some AVR chips you can use the Arduino bootloader but most chips come with a DFU bootloader that can support flashing over serial and USB. In the case of STM32, it additionally supports CAN, I2C, and SPI bootloading. For some reason the Nucleo boards don't have the native USB connector onboard, but the needed pins are available for easy access. (The discovery boards do.)

Connecting USB Pins

To access these pins you can use a USB breakout or a USB Tester. Of course you could always cut open a USB cable, but seriously, why create a mess? If you have one of my USB, Testers it makes it much easier, plus all of the other features it provides. BUY ONE NOW!! Just kidding! The pins for D+ and D- are not labeled on the pin out of the Nucleo board out but if you look up the datasheet you can find them and match the pin names with the Nucleo pin out as shown below.

So far I have tested the L152 and F411 and both have been PA12, PA11 (D+, D-). Which is pin 6,7 from the top on the right most column of male headers.

STM32 Nucleo USB DFU Connections

Saturday, May 23, 2015

Maker Faire, Bay Area 2015

This year the Bay Area Maker Faire celebrated ten years. William and I could not believe it! We've attended BAMF (as we cheekily call it), for the past eight years. Wow! It feels like only yesterday that we were frantically searching for parking, trying to stand in line before the gates opened. Oh wait, that happens each year. Ha!

This year was just as eye opening as ever. It has grown in popularity for sure, but more so it has also grown into a lot more than just garage hacking. From the new 3D Printer tent, to the Start-up area, the BAMF has become a fair that now encompasses so much more and will surely continue to morph. We feel like we've grown along with it. After-all, some of William's first blog posts were about the Arduino Projects Pack from MAKE.

We've certainly come a long way since the early days of the Maker Faire. For us, BAMF has become more than just the faire itself. It's a real treat to meet-up with some folks from around the globe that we now consider friends. Over the past couple of years, there have been some post Maker Faire shindigs like the BAMF meet-n-drink hosted by the Hackaday crew and the BringAHack dinner hosted by Laen from OSHpark. Honestly, it's really these outings that we look forward to attending. A chance to mingle without the distraction of a crowd or the barrier of a booth? We could do that all night!

I tried to capture some images from those evenings this year, but bare with me as it was dark and you know, after a long day with one or two beers, hiccups are bound to happen. :)

Sunday, May 3, 2015


Over the last few weekends and then some, I have been playing with the Colorific RGB Bulb from Amazon. Inspired by this learn guide I decided to make it reactive to audio. Finally! An excuse to buy the Teensy Audio shield!

Here are a few pictures and a short demo of it in action. You can find the code and my notes on the issues with it and where the project is at currently on:

Teensy 3.1 with Audio Shield, TFT connect to RPi

Raspberry Pi 2 with BT 4.0 and UART connected to Teensy 3.1.

Colorific Bulb in action

Monday, April 13, 2015

Review: Hummingboard

I came across the Hummingboard while reading Engadget. This isn’t your run-of-the-mill Linux board, it’s jam-packed with features that other boards don’t have. The main feature that sets this board apart from the others is that the SOC is socketed and swappable. What a great idea! Need more power for your project or different board features? Just swap out the SOC module or board and now you can have an expanded set of features all while using the same platform.

Does this new board look strangely familiar for some reason?
This board shares the same footprint and IO layout as the Raspberry PI.