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Author Topic: 8*8 led matrix with 74hc595  (Read 1020 times)
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i want to make LED screen using a lot of 8*8 led matrix  and i need to send data from arduino to show in it , i need simple code to show any letter on it , can i found library like lcd library,i need to use this matrix like lcd define the row and coulmn then send data will written and disappear if i clear it 
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One approach is to use a MAX7219 for each 8x8 matrix. $1.25 from taydaelectronics.com
They can be daisy chained so only a few arduino pins are needed to control them as one long chain.
http://www.taydaelectronics.com/catalogsearch/result/?q=max7219

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I finished  hardware connections with two 74hc595 for one 8*8 led matrix , i need simple code to set cursor then print data into led matrix or clear it or any library can help me
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Post your schematic, no one can offer code without seeing the hardware it is driving.
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schematic


* Arduino_LedMatrix_schematic.png (20.11 KB, 604x600 - viewed 73 times.)
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Any details on the matrix? Like which pins are anodes or cathodes?
As drawn, you should multiplex LED by LED.  Code was posted on doing just that over the weekend I believe.
The 74HC595 is only rated to sink/source 70mA total per the package; if you drive all 8 LEDs (in a columm or row) from 1 '595 with more than 8-9 mA, and sink all that current with 1 pin in the other '595, the 2nd '595 will see too much current.
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Any details on the matrix? Like which pins are anodes or cathodes?
As drawn, you should multiplex LED by LED.  Code was posted on doing just that over the weekend I believe.
The 74HC595 is only rated to sink/source 70mA total per the package; if you drive all 8 LEDs (in a columm or row) from 1 '595 with more than 8-9 mA, and sink all that current with 1 pin in the other '595, the 2nd '595 will see too much current.

Row anode
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