16x32-rgb-led-matrix-panel-to-a-raspberry-pi

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jonglee2018
 
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16x32-rgb-led-matrix-panel-to-a-raspberry-pi

Post by jonglee2018 »

https://learn.adafruit.com/connecting-a ... i?view=all

From the above link, I purchased all the required parts, but it seems the GPIO reference board is for Raspberry Pi model b which is discontinued. I only have the latest RASPBERRY PI 3 MODEL B. Please advise what I should do.

thanks
Jong

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Re: 16x32-rgb-led-matrix-panel-to-a-raspberry-pi

Post by adafruit_support_mike »

The connections are the same for all versions of the RasPi.

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jonglee2018
 
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Re: 16x32-rgb-led-matrix-panel-to-a-raspberry-pi

Post by jonglee2018 »

The problem is "GPIO reference board" does not fit Raspberry Pi 3 Model B.

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Re: 16x32-rgb-led-matrix-panel-to-a-raspberry-pi

Post by adafruit_support_mike »

The reference board doesn't do anything electrically, it's just a one-piece label you can use to identify the GPIO pins while you make connections.

All of the signal names on the first 2x13 chunk of a Pi3's GPIO header match the labels on the reference board. You can set it to one side and use it as a reference that way.

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jonglee2018
 
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Re: 16x32-rgb-led-matrix-panel-to-a-raspberry-pi

Post by jonglee2018 »

OK. I did the wiring. Now what do I do with "74AHCT125 - Quad Level-Shifter (3V to 5V)"?

The instruction says:

"These panels are designed to take 5V logic, and the Pi uses 3.3V logic. For some panels, the 3V logic is not high enough to trigger. If you're having difficulty you may need to use level shifting chips such as https://www.adafruit.com/product/1787 to shift the 3.3V up to 5V!"

But I can't even seem to find a place to use this piece. Any suggestions?

thanks for your help!

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Re: 16x32-rgb-led-matrix-panel-to-a-raspberry-pi

Post by adafruit_support_mike »

First, check to see if the matrix works without it. If it does, you don't need a level shifter.

If the matrix doesn't work with signals directly from the RasPi, you'll need to send them through a set of 74AHCT125s to convert the 0v-3.3V signals to 0V-5V signals.

Connect each of the signals from the RasPi to an input pin on a 74AHCT125, then connect the 74AHCT125's corresponding output pin to the LED matrix.

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