Good news, bad news, progress.

Let’s start with the good news!

IMG_0899I stripped a USB cable I had and soldered some solid core wire to it.IMG_0902It works just fine with any USB power source (5v). I taped up the connection, but I did it over again even tighter than what it looks like in the picture. I wanted to make it thick enough so it doesn’t flex a lot at that point because the wires in the USB cable are really tiny.

It’s hard talking about failures but they happen. Here’s the bad news, though it’s unrelated to this project:

IMG_0900I tried soldering the Atmega circuit to this prototyping board. It didn’t work.IMG_0901If you look closely, you’ll see the traces that are covered by the silkscreen. They throw me off a lot as I’m adding components on it. I have yet to have a successful project soldered on one of these boards, so I’m glad that this was my last one. I’m sticking to the perfboards with individual pads. I’ve had better experiences with them.

Now that the bad news is out of the way, let’s throw in some more good news!

My Dipmicro package shipped last night! I don’t expect it to arrive until early next week, though.

I found a stash of 9v batteries that I didn’t even know I had. I’ve been thinking of doing the “final” roaming robot, with the challenge of making it as small as possible since I learned to use the Atmega chip by itself. My biggest issue is power because it can’t be tethered to the wall and I don’t want to pour money into buying new batteries for it all the time. Since these robots are pretty much the only thing I’d power with batteries and I found four 9v batteries, there’s a better possibility of this happening.

One last thing… I still have to start the PLC Trainer program. I wrote up an old mixing tank situation last year so I’ll probably dig that up to get things going. I came up with the idea of using the new LED panel to show the tank level instead of using each LED to indicate the current state of the program. I’ll have more on that once I get to writing the plan out.


The Box: Prototyping

So “The Box” project is back, taking on a less ambitious form this time. I’m not going to try and cram every part I have into a box. It’s just going to be a simple temperature and humidity monitor with a clock and some LEDs. It’s nothing fancy, but I’m hoping I end up with a polished final product.IMG_0826I’ve begun prototyping all of the elements of the project together and I think I have a solid base right now. Let me walk through how the prototype currently works.

IMG_0831The system greets you when it’s first powered on. There is actually a reason for this which will be explained shortly.
IMG_0832This is the main screen. The clock can be toggled between 12 and 24 hour formats. The bottom line alternates between the temperature and humidity readings every three seconds.IMG_0835There’s the button to toggle the clock. The system is powered by a 9v power adapter into a 5v regulator. The brains is an Atmega328p microcontroller.IMG_0834Those two perfboards have the temperature/humidity sensor and the real time clock. Oh look, some LEDs!

The LEDs go back and forth signalling a complete second. It’s done using delays which provides a break for the LCD and sensor updating. While the LEDs are going back and forth, it isn’t actually using the RTC. It’s simply delayed so that a cycle back and forth takes a second.  This takes us to the reasoning for the power on screen with the “Hi”. What’s actually going on is there’s a delay so that you can always read the “Hi”, then it waits for the next second change by the RTC. This process syncs the start of the program with the start of a clock second. That way, every time the program loops back to the beginning, it starts at the top of a second since each loop of the program takes a second to complete.

Check out this video to see the prototype in action:

Light Timer Modification… Complete!

That went a lot smoother than I was expecting. This was more or less an overnight project. I started last night and completely finished and installed  today around 2pm. Here’s some pictures and details of the process.1The first thing I wanted to do was to get the photoresistor/light sensor working. It works fine, but I’ll have to monitor it for the next few days to make sure the sensitivity is appropriate.2The next step was to test out the Atmega circuit. It went well on the breadboard. The green LED is a power indicator and the push button is to reset the chip.3The sensor works in my completely darkened room. I’ll have to see how it reacts in the hallway.
4The final step was transferring everything onto a soldered prototyping board. I had this larger one lying around for a while. The more room to work with, the better.5I soldered the socket and power connections first.7The process continued until it was complete. I much prefer using these prototyping boards that already have rails/traces.6It was great to see it work as it did on the breadboard on the first power up. The adapter was giving the Arduino Uno board 9v. It’s a variable adapter so I dropped it down to 5v (hovers between 5.1v to 5.6v). I was thinking about adding a 5v regulator but I believe it will work fine since the adapter should be doing that already. I have more 9v battery connectors than I do AA/AAA cell holders so I’ll eventually have to start using the regulators in my projects.

So that’s it for the light timer modification! I plan on taking the real time clock circuit off of the breadboard and solder it onto a small prototyping board. It’ll likely be in use in the animatronic head project. I’m set to order more of the chips for the name tag project. Check out my previous post on a full list of my current projects. Thanks for reading!