repo2/ultimate_cart/veronica/bus_task.v @ 1475
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// bus_task.v
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// __
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// \\__/ o\ (C) 2014 Robert Finch, Stratford
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// \ __ / All rights reserved.
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// \/_// robfinch<remove>@finitron.ca
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// ||
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//
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// This source file is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published
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// by the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// This source file is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program. If not, see <http://www.gnu.org/licenses/>.
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//
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// ============================================================================
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//
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task opcode_read;
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begin
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vpa <= `TRUE;
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vda <= `TRUE;
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rwo <= `TRUE;
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ado <= pc;
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end
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endtask
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task insn_read;
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input [23:0] adr;
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begin
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vpa <= `TRUE;
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vda <= `FALSE;
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rwo <= `TRUE;
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ado <= adr;
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end
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endtask
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task data_read;
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input [23:0] adr;
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begin
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vpa <= `FALSE;
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vda <= `TRUE;
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rwo <= `TRUE;
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ado <= adr;
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end
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endtask
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task data_write;
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input [7:0] dat;
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begin
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vpa <= `FALSE;
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vda <= `TRUE;
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rwo <= `FALSE;
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ado <= wadr;
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dbo <= dat;
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end
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endtask
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task data_nack;
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begin
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vpa <= `FALSE;
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vda <= `FALSE;
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rwo <= `TRUE;
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ado <= 24'h000000;
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dbo <= 8'h00;
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end
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endtask
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