FPGA Development Board - strange shift operation behavior

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Hi,

Is your board an Altera/terasic dev board or a custom one based on Cyclone IV ? If its the Altera/terasic one, then most likely the LEDs are all active low , meaning, a writing a '0' will turn ON the LED and '1' will turn OFF the LED.

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Looks like custome Dev Board ZEOWAA A-C4E6E10.

Main problem in the part:

led <= (led << 1);

if I use explicit form like:

led <= (12'b000111011010 << 1);

it work pretty well on Dev Board.