David's #1 Gameboy (Pi3, Dual analog, Neopixel)[Update#3 Animated Neopixel charge status]

[dbak85]

So I was having some trouble with my batteries. I could not find anything that fit in the space I had left. So I bought 3 1200mah lipo cells (with integrated control circuit) and linked them in parallel.

After some research, I realised that this does not work properly and the Powerboost does not charge them properly when you do that(The Powerboost was not even getting warm, I was careful to get protected cells thankfully). I was getting 1hr20 of use before I got low batt warnings. So I decided the best option would be to properly make up a pack with a properly rated lipo protection circuit.

Dismantling the batteries
Be very careful if you attempt this.
I was aware of the risks of fire and damage if a short between the terminals occured

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I then connected the cells in parallel and connected them to the protection circuit rated 4A and masked it all up with kapton tape.

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I then went about finishing the pack with some padding for the part of the circuit that was overhanging and doing a full tape wrap.

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Initial tests on a second powerboost showed the pack worked and charged all the way. I then did a runtime test with supermario64.

Before pack assembly:
lowbatt after 1hr20min and shutdown at 1hr26min.

After pack assembly:
lowbatt after 2hr20min and shutdown after 2hr35min.

So yeah not bad, considering I have a screen a 1w amp and speaker and a Pi3 running at the same time.

[dbak85]

So finally it is done, we now have charge light animation!

At first I tried to use a transistor to get the charge status of the lights (after some advice from people on this forum )
But I just could not get it to work properly. Both leds from the powerboost would stay on when I had the transistor connected. So I eventually gave up and opted for some opto isolated mosfet relays(ASSR-1510), mostly due to space constraints and I wanted to completely isolate both sides of the circuit. Here is the diagram:

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When the leds come on they pull the pins on the teensy to ground and I use this to control the state of the neopixel.



Very happy with that

[Lololo]

I added the Sparkfun mono amp (It has a lot of line filtering with caps and there is no noise at all)

hello,

Can you explain to me what you did to filter the sound!

Thank you

[dbak85]

hello,

Can you explain to me what you did to filter the sound!

Thank you

nothing really I just used the mono amp from sparkfun. Using it with a 1w speaker there is not much noise. Notice I reviewed my statement, a lot of testing showed some, but not much noise on the speaker (You hardly hear it while playing). Testing with headphones was another story. There is a consistent whine during use.

I know of the problems with the pi3's audio. I cannot say if this amp is good in general or if I just got lucky with my amp and speaker combination

[Lololo]

Ok thanks for your reply...i will try your solution

[Hackmi]

This is awesome, I love how you did the buttons, I'll be sure to copy it.