A note on using ICSP: – The Square Inch is designed to accept an FTDI connection for programming. Because of this, a .1µF capacitor is between the reset line of the ATmega328P and the pin labeled DTR. This is so when you load new sketches on the Square Inch, it will reset automatically via the DTR line on the FTDI adapter. When you use ICSP, you need to bypass this capacitor! Otherwise it will not work. The programming board I used in the video had the capacitor bypassed with solder (pictured below). There is also a via to the right of the capacitor that leads to the reset line. This can be shorted to the DTR pin to accomplish the same task, as I did to program the assembled boards. Continue reading Programming the Square Inch – TQFP Jig
Hi peeps, I have been wanting to make a small GPS device (GPS receiver and some sort of screen) that I could carry around for a while now, but I didn’t want it to be too big, so I made this. Mission accomplished.
So I’m going up to NY in a few days, and I wanted a new and exciting way to talk with the TSA folks, so I figured this would work. (kidding) If only Hollywood had not trained everyone to think a gadget with a few wires and a flashing red LED, that they didn’t understand, was a bomb.. ugh. (not kidding)
*UPDATE – there is a set on Flickr for this with teardown pictures.
I have been working more with 3.3 volt projects lately and wanted to make programming them with an FTDI adapter as easy as possible. Sure you can switch most FTDI adapters from 3.3 to 5 volts (the FT232RL chip has a built in 3.3 output as well as logic level selection), but it involves scratching a jumper wire and soldering pads. This isn’t bad to do once, but to go back and forth is time consuming and rough on the boards.
So, I made my own FTDI adapter with an easily changed jumper for voltage selection. I also added a power LED to let me know that it’s plugged in and ready to go, threw in some RX and TX indicator LED’s and all required caps (read the data sheet), and mini SB jack. I ordered the boards from OHSPark.com, and as always, they were great.
I was inspired by a video by Jeri Ellsworth that showed her using homemade flux remover. This is super simple a combo of alcohol and acetone. In this video, I use a 50/50 combo of the two. So that’s 32 oz. of flux remover for $3. I Googled flux remover and it ranges from $10 to $25 for 12 oz. So that a savings of at least about $70. I have been using this on about every board I can find and it has worked great on all of them. I heart saving money. 🙂
This video above demonstrates the speed difference between serial enabled/disabled on an Arduino Uno while toggling a pin output. Just a really simple test of how fast it can pull a pin high and low (without using direct port manipulation), with and with out serial enabled. I think that was the smallest Arduino sketch I ever wrote..