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//============================================================================

//  BRANCH.v

//  Jcc disp8

//  - conditional branches

//  - fetch an 8 bit displacement and add into IP

//

//

//  (C) 2009-2012 Robert Finch

//  Stratford

//  robfinch<remove>@finitron.ca

//

//

// This source file is free software: you can redistribute it and/or modify 

// it under the terms of the GNU Lesser General Public License as published 

// by the Free Software Foundation, either version 3 of the License, or     

// (at your option) any later version.                                      

//                                                                          

// This source file is distributed in the hope that it will be useful,      

// but WITHOUT ANY WARRANTY; without even the implied warranty of           

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            

// GNU General Public License for more details.                             

//                                                                          

// You should have received a copy of the GNU General Public License        

// along with this program.  If not, see <http://www.gnu.org/licenses/>.    

//

//

//=============================================================================

//

// Fetch branch displacement if taking branch, otherwise skip

//

BRANCH1:

        if (take_br) begin

                code_read();

                state <= BRANCH2;

        end

        else begin

                ip <= ip_inc;

                state <= IFETCH;

        end

BRANCH2:

        if (ack_i) begin

                term_code_read();

                disp16 <= {{8{dat_i[7]}},dat_i};

                state <= BRANCH3;

        end

BRANCH3:

        begin

                ip <= ip + disp16;

                state <= IFETCH;

        end