I am using TLC 5940 PWM with 74HC595 scanning in a 24X8 RGB LED matrix.
With Arduino Mega 2650.
24 RGB lines control by TLC 5940 and 8 rows scanning by 74HC595.
shiftOut() and TLC.update() for send data. (using TLC5940.h )
TLC.update() bleeding to next row. Raw scanning with 1ms delay.
When I slow down more than 30ms, no bleeding. Its comes to effect when I speed up the scanning.
Looks like TLC.update() is bit much slow and pending updates bead to next raw.
You need to synchronize the row changes to the TLC PWM cycle.
The TLC library isn't really designed for that, you'll have to modify it. Maybe you could change row at the beginning of the the TLC library interrupt handler.
Now working with TLC5940.h , getting much better. Only small issue. Raw 3 and raw 7 not functioning. Just in off condition.others are fine. I have started a new thread for the issue. Thx everyone for the support given. I will post all diagrams and codes ones I get it working.
Mega 2560, TLC5940, 74hc595 and TLCMux library....
If someone interesting, still no luck. Now Trying to drive the both TLC and shift reg. from Hardware SPI, not using any libraries and update the LEDs in timer interrupt. Shiftout is slow. Can I use both TLC5490 and the 74hc595 in same SPI ?