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Naked Breadboards



I did it!  ...I finally removed all of those projects... I finally stripped those breadboards bare.

I hate breadboards. But sometimes I still use them when I want to prototype something that I don't understand.  I am a noob at this electronics thing. There are times (a lot of them) where I need to stick a couple of parts on a board take some measures and see what happens and the breadboards are sometimes good for that.

I have been extremely busy at work for the last 18 months. So busy that work has greatly intruded into my free time. I had quite a few RF projects & experiments in flight some of which were on those breadboards. I noticed at least two QRSS transmitters with 10.140mhz crystals. I noticed at least one 7mhz QRP transmitter & pa based upon the crystal and NPN BJTs on the board.  --Who really knows what each of those things was supposed to represent as it was so long ago that it is beyond a blur.

It finally hit me yesterday when I was trying to prototype something with my Arduino Uno and I had no open breadboards to work with.

This afternoon I removed all of the components. Now I have the chore of sorting those parts and returning as many of them as possible back into their proper parts bins.

I take the last couple weeks of cleaning & sorting (for a few minutes at a time) as an indication that I am about ready to start the winter RF building season. It is kind of like the geese migrating south for the winter flying in their classic V formations, my cleaning of the work bench and the acquisition of parts from Digikey, Mouser, Dan's Small Parts, and eBay is a sign that RF construction season is near by.

73 de NG0R

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Arduino - Hello World



I figured that I needed to do the standard "Hello World" tests with the LCD since this was a new platform for me. To be real honest it took me longer to wire up the leads to spare LCD than anything else and even that did not take more than about 15 minutes.

Parts:
A short section of cat 5 (so that jumper wires are easier to track with some color variation)
10k ohm pot
10 ohm resistor
16x2 LCD
Arduino Uno

The online notes that I referenced for this tutorial omitted the circuit details for wiring up the LCD backlight (aka: the LED on pins 15 & 16) but a couple of quick searches resolved that little detail.





I also wanted to take the experiment and draw it out in Fritzing to see how well it would help visualize the example for the web. It was pretty easy for using it for the first time. The picture above took about 10 minutes to draw out.

For the code I used the Hello World example sketch. Once that was working (first try) I made a quick tweak to it and sent it back to the board for pictures.

---------------------

/*
  LiquidCrystal Library - Hello World, NG0R
 
 Demonstrates the use a 16x2 LCD display.  The LiquidCrystal
 library works with all LCD displays that are compatible with the
 Hitachi HD44780 driver. There are many of them out there, and you
 can usually tell them by the 16-pin interface.
 
  The circuit:
 * LCD RS pin to digital pin 12
 * LCD Enable pin to digital pin 11
 * LCD D4 pin to digital pin 5
 * LCD D5 pin to digital pin 4
 * LCD D6 pin to digital pin 3
 * LCD D7 pin to digital pin 2
 * LCD R/W pin to ground
 * 10K resistor:
 * ends to +5V and ground
 * wiper to LCD VO pin (pin 3)
 
 This example code is in the public domain.

 http://www.arduino.cc/en/Tutorial/LiquidCrystal
 */

// include the library code:
#include

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {
  // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.print("Hello from NG0R!");
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(0, 1);
  // print the number of seconds since reset:
  lcd.print(millis()/1000);
}

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Overall it was a pretty easy experience.  It worked as expected (a novel idea) which helps to grow your confidence level. I am pretty impressed with the tutorials and examples. The Arduino team has done a good job creating a tool that has a low barrier to entry.

73 de NG0R

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Schematics and images for documentation

When I am working on a electrical or RF design project I like to create nice documentation for the effort. Frequently I am sharing my ideas with friends over the Internet as I work through the iterative design process. Creating those images usually has been either JPG exports or screen-captures from my schematic capture or PCB design software. (Things like TinyCad, Free PCB, PCB Express, Eagle, KiCad, etc)


Today I was reading a tutorial at: http://arduino.cc/en/Tutorial/LiquidCrystal
and I noticed the nice visual (physical) representation of the circuit.  I noticed that it was created with a tool called Fritzing. http://fritzing.org/


It turns out that Fritzing is an Open Source project. It allows you to draw images like the one above, it does the schematic capture, and PCB layout with auto-routing.  It appears that you can export the files as images to web, gerber, and also send them to fab houses. --The tool will run on Windows, Mac, and Linux.

I installed it on my Ubuntu 11.10 64bit machine and had it running in about 2 minutes. I am going to work on an Arduino tutorial today (I am still getting my feet wet with the platform) and as part of that effort I will try to draw out the project with Fritzing to see what it can do. I see a lot of potential for this tool if it performs well.

73 de NG0R


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Starting Arduino with Ubuntu

I decided that I would spend a little time today getting to know my Arduino Uno development board.

I have worked with PIC processors in the past and have several prototyping and programming boards for that platform but I have never worked with the ATMEL AVR or Arduino platforms. "Naked AVR" and Arduino are both very popular with a lot of tutorials on the Internet. I had ordered an Arduino Uno board much earlier in the year but had not done anything with it until today.

I am running Ubuntu 11.10 in my office and radio room and 11.04 at my electrical workbench. To install the Arduino development environment you can go to the Linux Software Center (add/remove program equivalent for the windows folks out there) and search for Arduino. There is a fairly current version of the tools in the repository and click install.




I plugged in my USB cable from the PC to the Arduino but you will need to know what USB port it was assigned. So ran the command dmesg | tail -2  which gives me the last 2 lines of the "display message" or "drive message" info for when I connected the Arduino.  On my system it came up as ttyACM0

watch "dmesg |tail -15"    --would work well for this too



I fired up the development tools, saved a new blank sketch called sketch_blink and then grab the blink example and copy/paste the code into my sketch. I then used the upload tool to send the code to ttyACM0


Here is a picture of my Arduino with the LED on pin13 blinking. (Your basic hello world kind of program)


While this is not very exciting it did validate that my Linux workstation running Ubuntu 11.10 64bit could talk to my Arduino Uno board and upload a program to it.  The whole time end-to-end was less than 10 minutes for all of the things that I listed above... that was my first time trying this. (aka: pretty simple)

This is much easier than my last experience working with the PIC platform and Ubuntu.

I will be spending some time reading the large amount of examples & tutorials on the internet so that I can get up to speed on the platform, keywords, and working with the "C" development environment. I have some project that are in need of a MCU for control and feedback.

Once I have the basics under control I will probably look at the AVR-GCC toolchain. I think that it can be installed via: sudo apt-get install gcc-avr binutils-avr gdb-avr avr-libc avrdude

73 de NG0R