Subversion Repositories rtf8088

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

//  CALL FAR and CALL FAR indirect

//

//

//  2009-2013 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/>.    

//

//

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

//

CALLF:

        begin

                write(`CT_WRMEM,sssp,cs[15:8]);

                lock_o <= 1'b1;

                state <= CALLF1;

        end

CALLF1:

        if (ack_i) begin

                pause_stack_push();

                state <= CALLF2;

        end

CALLF2:

        begin

                write(`CT_WRMEM,sssp,cs[7:0]);

                state <= CALLF3;

        end

CALLF3:

        if (ack_i) begin

                pause_stack_push();

                state <= CALLF4;

        end

CALLF4:

        begin

                write(`CT_WRMEM,sssp,ip[15:8]);

                state <= CALLF5;

        end

CALLF5:

        if (ack_i) begin

                pause_stack_push();

                state <= CALLF6;

        end

CALLF6:

        begin

                write(`CT_WRMEM,sssp,ip[7:0]);

                state <= CALLF7;

        end

CALLF7:

        if (ack_i) begin

                nack();

                if (ir==8'hFF && rrr==3'b011)   // CALL FAR indirect

                        state <= JUMP_VECTOR1;

                else begin

                        cs <= selector;

                        ip <= offset;

                        state <= IFETCH;

                end

        end