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Raspberry Pi Zero Gameboy

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BlueNostromo

Member
Joined
Mar 24, 2015
So i purchased a few Raspberry Pi Zeroes a few days ago and I have RetroPie running on one of them. I have purchased this display (3.5" touch screen that uses the 40 pins) http://www.ebay.com/itm/221868026906?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

The only way I have seen people connect controllers is using the same 40 pins. I doubt I can wire up the controller and the screen to those pins at the same time, so I guess I would be forced to use USB?
 

NiHaoMike

dBa Member
Joined
Mar 1, 2013
You have to note which pins the display actually uses. Then make sure the buttons are connected to GPIOs not used by the display.
 
OP
BlueNostromo

BlueNostromo

Member
Joined
Mar 24, 2015
Raspberry-Pi-GPIO-Layout-Model-B-Plus-rotated-2700x900.png

The display uses pins 1-26. Leaving me the other 14. From what I gather I cannot use the ID_SD pins for my use. That leaves me with 9 IO pins (the green ones right?). I can connect any or all of these green pins to the 3 common ground pins to use them as buttons?
 

NiHaoMike

dBa Member
Joined
Mar 1, 2013
Connect the buttons between the GPIOs and ground. Also add 10k pullups from each GPIO used for buttons to the 3.3v supply

You'll probably want to save the USB for other purposes like plugging in a USB drive to save games onto.
 
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BlueNostromo

BlueNostromo

Member
Joined
Mar 24, 2015
Also add 10k pullups from each GPIO used for buttons to the 3.3v supply

I have a 32gb sd card so space should be a non-issue. You are saying add a resistor connecting the GPIO being used and 3.3v? What is the reason for this?
 
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OP
BlueNostromo

BlueNostromo

Member
Joined
Mar 24, 2015
So the system will think "if not receieving 3.3V on GPIO 'x', then 'x' button is pressed"?