Computes one of the 16 possible two-variable (dyadic) Boolean operations,
selectable at run-time, on the A
and B
input words.
We implement the operator by using a multiplexer differently: each
corresponding bit from the A
and B
inputs, taken together as a 2-bit
number, selects one of the bits of a 4-bit truth table input to the
multiplexer which describes the Boolean function.
For example, if we take the corresponding bits of A
and B
as the 2-bit
number {A,B}
(i.e.: where the bit from A is the most-significant bit),
then the binary truth table 1000
describes the AND
Boolean operation,
as only bit 3 of the truth table is set. For readability, you can include
a list of the possible truth tables
before using this module.
This module is useful in ALU designs for data processing and in control logic to set expected conditions that must be met (e.g.: CPU branch logic, industrial process control).
`include "Dyadic_Boolean_Operations.vh" `default_nettype none module Dyadic_Boolean_Operator #( parameter WORD_WIDTH = 0 ) ( input wire [`DYADIC_TRUTH_TABLE_WIDTH-1:0] truth_table, input wire [WORD_WIDTH-1:0] word_A, input wire [WORD_WIDTH-1:0] word_B, output wire [WORD_WIDTH-1:0] result ); generate genvar i; for(i = 0; i < WORD_WIDTH; i = i+1) begin: per_bit Multiplexer_Binary_Behavioural #( .WORD_WIDTH (1), .ADDR_WIDTH (`DYADIC_SELECTOR_WIDTH), .INPUT_COUNT (`DYADIC_TRUTH_TABLE_WIDTH) ) Boolean_Operator ( .selector ({word_A[i],word_B[i]}), .words_in (truth_table), .word_out (result[i]) ); end endgenerate endmodule