mirror of
https://github.com/sxpert/hp-saturn
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cbfbe4eb3f
add add_cst and sub_cst alu opcodes port pointer math to use ALU make A[ab]x more readable
28 lines
548 B
Verilog
28 lines
548 B
Verilog
/******************************************************************************
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* Cx
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* maths...
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*
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*/
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`include "decstates.v"
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`DEC_CX: begin
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case (nb_in)
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4'hA: begin
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if (!hex_dec) begin
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{Carry, A[19:0]} = A[19:0] + C[19:0];
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decstate <= `DEC_START;
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end
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`ifdef SIM
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$display("%5h A=A+C\tA%s", inst_start_PC, hex_dec?"\t\t\t <=== DEC MODE NOT IMPLEMENTED":"");
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`endif
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end
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default: begin
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$display("ERROR : DEC_CX");
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decode_error <= 1;
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end
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endcase
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end
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