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Altera_Forum's avatar
Altera_Forum
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16 years ago

VHDL: inout port error: multiple drivers

Hello, I have defined an entity with some ports. One of these ports is defined as follows: data : inout std_logic_vector (63 downto 0); As you see, I want to read from or wr...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

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You never need internal inout ports.

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They are convenient in some cases though. They are available VHDL constructs and well supported by Quartus. For me, they are a means to wire global data and parameters through the design hierarchies with minimal code typing effort. But there can be only one driver for each data entity, of course