Using Shift register (74hc595) in LARGE led matrix

Started by 2011...@iiitdmj.ac.in August 23, 2012
Dear all,
I made a LED matrix (8x14) using atmega8L without using any shift register, to make it larger (CASCADING) i need to use shift register.
I have seen many tutorials but none has provided the code,
So if any one can provide me the code (or atleast the shifting function ) I will be very thankful.
I know the concept of POV, as i have already made a working LED matrix ,
I JUST NEED TO LEARN HOW TO SHIFT THE COLUMNS THROUGH THE 8-BIT SHIFT REGISTER TO PRODUCE SCROLLING EFFECT
Hi,
if you use the 74hc164, witch have a serial data & clock inputs and 8 // data outputs, you use 2 IO lines to transfer data to the shift reg. : put the data bit on the S.R.Di then send a pulse to clock input of S.R, then shift left (or right ) the data register inside MCU, repeat 8 times for each byte.
cascading S.R : connect all clocks input to mcu IO line (named clock). connect Data in of 1st S.R to mcu IO line (named Data) connect data input of next SH to the data output of the 1st.
Somme designer use scan method which light one  line or one colon of leds at a moment, in this case you must scan all colons 30 times / sec or faster.

you need rows count  + colons count lines to drive all leds. the current of each led is colons count times  grater than nominal Led current (limited by max pulse current conditions ), you can use drivers as UNL2003 (7 NPN darlington 500ma /output - 600 ma by IC )

________________________________
From: "2...@iiitdmj.ac.in" <2...@iiitdmj.ac.in>
To: a...
Sent: Thursday, August 23, 2012 7:08 AM
Subject: [AVR club] Using Shift register (74hc595) in LARGE led matrix


 
Dear all,
I made a LED matrix (8x14) using atmega8L without using any shift register, to make it larger (CASCADING) i need to use shift register.
I have seen many tutorials but none has provided the code,
So if any one can provide me the code (or atleast the shifting function ) I will be very thankful.
I know the concept of POV, as i have already made a working LED matrix ,
I JUST NEED TO LEARN HOW TO SHIFT THE COLUMNS THROUGH THE 8-BIT SHIFT REGISTER TO PRODUCE SCROLLING EFFECT