Parallel port has >50kB/s bandwidth easily.
Your design requires a refresh rate spec and allowed latency, supply power source and LED Vf @If specs.
If 0.5ms is allowed then refresh rate is 2kHz then parallel rate is 25kHz x8bit /
Serial encoder/decoder would require 100 x 2kHz rate. If you need to latch the LED state, a serial clock and data port with a start trigger would seem to be the best approach.
You may want to think about using parity or error detection.
A 3.3V supply would be more efficient.
You need to define the allowed latency from time to display and if sync error from 1st to last LED if permitted. e.g. raster update mode or parallel load.
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Hi
thanks alot
what you wrote sounds interesting, but I did not fully get it and I would like to explain more
HardWare : I have LED matrix (100 LED ( width) X 100 LED (height))
SoftWare: on hard disk I have many random size colored images files and using vb.net I converted one of these images into an image file of black and white pixels only - why ? in order to send this image into the LED matrix, the final image size is always ( 100 pixel width X 100 pixel height), I did image processing to convert any image on harddisk into 100 pixel X 100 pixel to send it to the LED matrix.
what I need to do is to send this image file of black and white dots into the corresponding LED and make this image scroll down on the LED matrix. for example pixel (0,0) should be sent to LED(0,0) and make it ON -if pixel is WHITE or OFF-if pixel is BLACK, pixel(1,0) should be sent to LED(1,0) until I reach pixel ( 100,100) should be sent to LED(100,100)
I need a method either parallel or serial to send these pixels(either black which is 0 or white which is 1 ) to its corresponding LED to make it ON or OFF , also I need to crawl down the image , what I mean I need this image to move from up of the LED matrix and crawl down to the end of the LED matrix.
and how I can control the speed of crawling ?
would you please explain more ? or a book or example
Thanks alot