hp-saturn/saturn_bus_controller.v
2019-02-25 09:17:17 +01:00

72 lines
No EOL
1.5 KiB
Verilog

/*
(c) Raphaël Jacquot 2019
This file is part of hp_saturn.
hp_saturn is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
any later version.
hp_saturn 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 Foobar. If not, see <https://www.gnu.org/licenses/>.
*/
`default_nettype none
module saturn_bus_controller (
i_clk,
i_reset,
i_phases,
i_phase,
i_cycle_ctr,
o_bus_clk_en,
o_bus_is_data,
o_bus_nibble_out,
i_bus_nibble_in,
o_debug_cycle,
o_halt
);
input wire [0:0] i_clk;
input wire [0:0] i_reset;
input wire [3:0] i_phases;
input wire [1:0] i_phase;
input wire [31:0] i_cycle_ctr;
output reg [0:0] o_bus_clk_en;
output reg [0:0] o_bus_is_data;
output reg [3:0] o_bus_nibble_out;
input wire [3:0] i_bus_nibble_in;
output wire [0:0] o_debug_cycle;
output wire [0:0] o_halt;
reg [0:0] bus_error;
initial bus_error = 0;
// this should come from the debugger
assign o_debug_cycle = 1'b0;
assign o_halt = bus_error;
always @(posedge i_clk) begin
if (!o_debug_cycle) begin
end
if (i_reset) begin
bus_error <= 1'b0;
end
end
endmodule