Difference between revisions of "Adafruit: Bicolor LED Square Pixel Matrix"

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<pre style="color:red">
 
<pre style="color:red">
 
Overview: 2
 
Overview: 2
Wiring:  0
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Wiring:  1
Code:    1
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Code:    1, should have called ioctl directly
git/Compiles with make: 0
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git/Compiles with make: 2
Demo:    0
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Demo:    2
Total:    3
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Total:    8-1(late) = 7
Comments: It's good you have it working.  Now you need to fix up this page.
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Comments: It works, but it isn't pretty.
Assume you are writing to someone who wants to know how to use the device.  Show a picture
 
of it. Note the importance of soldering the display on correctly. Give wiring instructions.
 
Be specific, where do I wire the power?  Where does the clock go, etc.  How is the voltage
 
level converter wired in? Show a picture of the wiring.
 
 
 
Clean up Greg's code an put it in your github repository. Include a Makefile
 
Give me a demo.
 
 
 
Can you have this done in a week?  24-Oct-2012?
 
 
</pre>
 
</pre>
  
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== Summary ==
 
== Summary ==
 
This page details project work done while working on the 8x8 Bicolor LED Pixel Matrix from Adafruit found here: [https://www.adafruit.com/products/902 Store Link]
 
This page details project work done while working on the 8x8 Bicolor LED Pixel Matrix from Adafruit found here: [https://www.adafruit.com/products/902 Store Link]
 +
 +
This device responds to standard I2C write and Read commands on the 3rd I2C Device at 0x70 device address.
 +
  
 
IMPORTANT!!! When soldering the led matrix to the controller make sure that it is placed correctly. If it is not, then the device will still communicate but the LED Matrix will not turn on.
 
IMPORTANT!!! When soldering the led matrix to the controller make sure that it is placed correctly. If it is not, then the device will still communicate but the LED Matrix will not turn on.
  
 
== Wiring Information ==
 
== Wiring Information ==
The device relies on the 5V source on the board and to insure functionality an I2C voltage up-converter is used to boost the 3.3V I2C voltage to 5V.  
+
The device relies on the 5V source on the board and to insure functionality an I2C voltage
 +
level converter is used to boost the 3.3V I2C voltage to 5V. The voltage
 +
level converter is hooked up according to the photo. Starting from the top left of the device: SCL 5V, 5V Rail, Reset(Pulled up to 3.3V), SCL 3.3V In. Bottom Left: SDA 5V, Ground, 3.3V, SDA 3.3V.
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 +
The LED Matrix is wired from left to right: 5V, Ground, SDA, SCL.
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 +
The tenth pin from the Right on row 1 of the P9 IO Rail on the Beagle (Count from the 5V Line in) is the SCL pin and the pin on row 2 is the SDA pin. Starting from the right on P9 top row is: Ground, 3.3V, Skip, 5V.
 +
 
 +
<span style="color:red">The wiring instructions are hard to follow.  Which header on the bone are you using?  P9?</span>
  
 
[[File:MiniProject2WiringDiagram.png|200px|thumb|left|Wiring Diagram]]
 
[[File:MiniProject2WiringDiagram.png|200px|thumb|left|Wiring Diagram]]
  
== Current Status ==
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== Code ==
The current LED Matrix is fully functional except for a minor issue with alignment of the rows. It is shifted up by one LED and puts the top row at the bottom. The former issues encountered with the device was due to a miss-wiring of the matrix to the I2C Part.
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The code is hosted on github here: [https://github.com/draneaw/MiniProject2 8x8 Led Grid Basic Code]
 +
 
 +
<span style="color:red">You should have called iotcl directly rather than using i2cset</span>
 +
 
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This is a very simple code implementation that is only to verify that the matrix works. For a further implementation of the 8x8 Matrix see the Mini Project 4 project here: [https://github.com/draneaw/MiniProject4.git Node.js Advanced Implementation]

Latest revision as of 12:09, 14 November 2012


Overview: 2
Wiring:   1
Code:     1, should have called ioctl directly
git/Compiles with make: 2
Demo:     2
Total:    8-1(late) = 7
Comments: It works, but it isn't pretty.

thumb‎ Embedded Linux Class by Mark A. Yoder


Page by Alex Drane, Peter Ngo

Summary

This page details project work done while working on the 8x8 Bicolor LED Pixel Matrix from Adafruit found here: Store Link

This device responds to standard I2C write and Read commands on the 3rd I2C Device at 0x70 device address.


IMPORTANT!!! When soldering the led matrix to the controller make sure that it is placed correctly. If it is not, then the device will still communicate but the LED Matrix will not turn on.

Wiring Information

The device relies on the 5V source on the board and to insure functionality an I2C voltage level converter is used to boost the 3.3V I2C voltage to 5V. The voltage level converter is hooked up according to the photo. Starting from the top left of the device: SCL 5V, 5V Rail, Reset(Pulled up to 3.3V), SCL 3.3V In. Bottom Left: SDA 5V, Ground, 3.3V, SDA 3.3V.

The LED Matrix is wired from left to right: 5V, Ground, SDA, SCL.

The tenth pin from the Right on row 1 of the P9 IO Rail on the Beagle (Count from the 5V Line in) is the SCL pin and the pin on row 2 is the SDA pin. Starting from the right on P9 top row is: Ground, 3.3V, Skip, 5V.

The wiring instructions are hard to follow. Which header on the bone are you using? P9?

Wiring Diagram

Code

The code is hosted on github here: 8x8 Led Grid Basic Code

You should have called iotcl directly rather than using i2cset

This is a very simple code implementation that is only to verify that the matrix works. For a further implementation of the 8x8 Matrix see the Mini Project 4 project here: Node.js Advanced Implementation