8,32 bit Selectors

When passing data around to different destinations, we need to select where it goes.  There is an opcode that selects the operational unit.  The input registers are decoded from the operands, and directed using selectors to push the input to the operator component.  After decode happens, the pathway is enabled by data path selectors.  Here is an 8 bit selector.

You can see we use tri-state gates only send the output when the select line is enabled.  When not selected, the output's are tri-stated and won't interfere with the input they are connected to.  This way we can have many selectors connected to a common input line without interference.

With the 8 bit selector we build up a 32bit to help shuttle our data around.