matriz led lpt
syrax said:
i wanna make slow animation with 5 Hz can i use 74hc595 or will be too slow for this . I think on this to put some MCU-s and they to comunicate via serial port to make this little faster
I think you are talking of two different things here.
1 - To light the LED matrix at all in a way it will look stable you need to update it at least 50 times/second, preferably a bit faster. This means scanning 10000 LEDs 50 times or address 500,000 LEDs each second. This, just to see a stable picture.
2 - To animate this you'll need to CHANGE the display contents a number of times each second, but the number of LEDs scanned does not change by this, only the pattern you put out. For each frame(picture) you put out you need 1250 bytes to represent 10000 LEDs as a minimum.
The main job is to make light in the matrix at all. The animation is a minor problem after that.
If you use hardware in a direct way, you'll need to put out 100 bit each 200us to scan with 50Hz. I would think the only way to do this is to use a memory mapped parallel system, maybe with a double set of registers to make instant transfer of data. Load1 - switch - load2 - switch - load1 ... and so on. It should be possible to do this with a relative fast micro.
If you use preloaded data for the different frames you should manage a slow animation too, with 'cycle stealing' for loading the next frame.
To do this you'll need very effective code, so forget Basic.
TOK