we use
1-pic16f628a as microcontroller :cheap,program memory 2k,has internal oscillatror,two ports A,B and alot of things.
2-led matrix 8*8 rows common anode and columns common cathode
3-shift register i use 74ls164 it is simple than 74595 his job is scanning columns activate one at atime
4-uln 2803
every time maximum of eight led work so current=8*(15ma for every led=120ma
shift register can't sink this much current so we use uln .it can sink current up to 500ma
5-eight resistors 120ohm,pack resistors 10k
The Complete Circuit diagram is Shown
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Signing UpStep 1Led matrix construction
to light aspecfic led we apply logic high(1) to anode and logic zero to cathode
so we make anode as data source and cathode as scanning (activate cathode of aspecfic column) so we connect anodes(rows) to portb and cathodes to uln and shift register
we discuss this later
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You don't want to move the words isn't it you want to display words only and not move