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Altera_Forum's avatar
Altera_Forum
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18 years ago

Can't resolve multiple constant drivers?

I'm really confused. I'm trying to make a barrel rotator but Quartus is complaining about my VHDL. This is the line it points to: SIGNAL alu: STD_LOGIC_VECTOR(15 DOWNTO 0); but I see nothin...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

Perhaps it's my use of muxes? I'm trying to redo my 2:1 mux but I'm having trouble getting it to compile. 

ARCHITECTURE Behavior OF VHDLMux21 IS
SIGNAL output : STD_LOGIC_VECTOR(15 downto 0);
PROCESS(a,b,s)
BEGIN
IF s = '0' THEN
   output <= a;
ELSE
   output <= b;
END IF;
END PROCESS;
c <= output; 
END Behavior;