Raspberry Pi Zero Gameboy

BlueNostromo

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Joined

Mar 24, 2015

• Apr 12, 2016

• #1

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

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Joined

Mar 1, 2013

• Apr 13, 2016

• #2

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

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Joined

Mar 24, 2015

• Apr 13, 2016

• Thread Starter
• #3

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?

 

OP

BlueNostromo

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Joined

Mar 24, 2015

• Apr 13, 2016

• Thread Starter
• #4

I dunno, I am not good with circuit boards or coding... So Ill just use USB!

 

NiHaoMike

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Joined

Mar 1, 2013

• Apr 14, 2016

• #5

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.

 

OP

BlueNostromo

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Joined

Mar 24, 2015

• Apr 14, 2016

• Thread Starter
• #6

NiHaoMike said:

Also add 10k pullups from each GPIO used for buttons to the 3.3v supply

Click to expand...

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?

 

Last edited: Apr 14, 2016

NiHaoMike

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Joined

Mar 1, 2013

• Apr 15, 2016

• #7

So when the button is not pressed, the GPIO gets pulled to the supply voltage.

 

OP

BlueNostromo

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Joined

Mar 24, 2015

• Apr 15, 2016

• Thread Starter
• #8

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