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Dustin' off the old breadboard

Ah, back to university at last! Don't get me wrong, summer has been great but nothing beats Linköping.
Anyhow - about a year ago a friend wanted to create a special clock in order to measure the time it takes to empty a bottle. Initially he was going to use NAND-gates, but after showing him the price differences between using NAND-gates and an AVR we both agreed to use an ATtiny861.

Fast forward to today. We finally got to work by rigging everything and started assembling parts on my breadboard. Since I had a couple of ATmega644P laying around we upgraded to using that for now - we will see if the design will fit into an ATtiny861 in the end, I am doubtful at this stage.

I haven't used the ATmega644P a lot, but I have never had any problem with the special port functions being active by default. We had some weird problems with PORTC{2-7} outputting some sort of fast oscillating signal even though the execution was caught in a while(true);. For now we switched to using PORTC0 and PORTC1 - will investigate further when the LCD-display is correctly interfaced.

What we currently have accomplished is that the LCD-display shows "Redo" ("Ready") when the MCU loses power - kind of odd but I think it is caused by intensive screen clearing without wait for screen updates. We will see tomorrow!

For now, here's a bit rough photo of the setup. Also attached is the signals analyzed when we got everything working.

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