Project: bug-bot

Recently my daughter brought a journal from the local library. There was a bug bot my daughter said she wanted to make and it was dead simple. There was just one problem with that – I did not get how it could work at all – there was just a solar cell and the vibration motor just connected directly. The motor needs like constant 60mA of current, how is that possible that a tiny solar cell can provide that?

So I ordered cheap motors and cheap solar cells from a you-know-the-name website and guess what, it did not work.

two bots
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Pic Lab. PIC18. Experiment #6. Touch sensor using ADC

Task: To study the possibility of using of the DIY touch capacitive sensor on the pcb

Tools: PIC18f1230, a pcb with exposed square copper areas

So long story short, my cheap amazon lamp did not survive for a long time, but I really did like the LED light it gave. In the article below I will describe how to use a copper pad and the pic microcontroller without much additional circuitry.

Touch sensor touched and untouched

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Pic Lab, PIC18, Experiment #1.1, UART / USART (updated version)

Recently, I was constantly struggling with the fact that microchip was removing more and more support libraries, so it was not wise to rely on them in all projects. Anytime I return again to my old functions – if it used the support libs, there is a pretty good chance it is screwed.

So this code works with XC8 version 2.36 and doesn’t require the involvement of extra support lib.

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Pic Lab, PIC18, Experiment #5, USB

When I started to dig into USB topic it was quite a surprise, the amount of efforts the smart people around the world put into it just unbelievable. Even more fascinating fact – it actually worked out. The excitement reached some saturation when I realized the prices (: Vendor ID will cost you 5 grands per year, want to use a USB logo – no problem, just add another 6 grands on the top. Now we could test the compliance of your device with our standard for n grands… The companies using USB are listed on the website (USB Implementers Forum – USB-IF). The curious one could just count a number of companies and calculate the profit just from the year subscription, and this thing is going on for a long long time already. Well they have definitely built an addictive stuff. I, personally, have found the usage for my projects a bit excessive, I definitely not ready to put 5 grands per year for USB in the cheap humidity sensor.

Now, there are tons of different information, it is really challenging to grasp all at once, I will be honest and won’t pretend that I got everything, have a lot of holes in the knowledge, I just need to make it alive and respond to my commands. So, what I gonna to do is to show the info which looked important to me and then will conduct two experiments on this “foundation”.

USB diagram
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Pic Lab, PIC18, Experiment #3, ADC

I was working on a small project where I needed to catch a certain button pressed event. Sounds simple initially, but I have 10 such buttons and it means that I need to have 10 IOs, or port expander, or make a digital matrix button handler (like 3×4 keypad) but these all variants are boring, I wanted something more interesting and make something like a DAC based on these buttons which will be digitazed by the built-in ADC in pic18f14k50. Thus, we will use a single port instead of 10, by cost of the more complicated code.

Let me start as usual – from reading of the datasheet.

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