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diff --git a/fpga/usrp2/control_lib/ram_harvard2.v b/fpga/usrp2/control_lib/ram_harvard2.v
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+//
+// Copyright 2011 Ettus Research LLC
+//
+// This program 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
+// (at your option) any later version.
+//
+// This program 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/>.
+//
+
+
+
+// Dual ported, Harvard architecture
+
+module ram_harvard2
+ #(parameter AWIDTH=15,
+ parameter RAM_SIZE=32768)
+ (input wb_clk_i,
+ input wb_rst_i,
+ // Instruction fetch port.
+ input [AWIDTH-1:0] if_adr,
+ output reg [31:0] if_data,
+ // Data access port.
+ input [AWIDTH-1:0] dwb_adr_i,
+ input [31:0] dwb_dat_i,
+ output reg [31:0] dwb_dat_o,
+ input dwb_we_i,
+ output dwb_ack_o,
+ input dwb_stb_i,
+ input [3:0] dwb_sel_i);
+
+ reg ack_d1;
+ reg stb_d1;
+
+ assign dwb_ack_o = dwb_stb_i & (dwb_we_i | (stb_d1 & ~ack_d1));
+
+ always @(posedge wb_clk_i)
+ if(wb_rst_i)
+ ack_d1 <= 1'b0;
+ else
+ ack_d1 <= dwb_ack_o;
+
+ always @(posedge wb_clk_i)
+ if(wb_rst_i)
+ stb_d1 <= 0;
+ else
+ stb_d1 <= dwb_stb_i;
+
+ reg [7:0] ram0 [0:(RAM_SIZE/4)-1];
+ reg [7:0] ram1 [0:(RAM_SIZE/4)-1];
+ reg [7:0] ram2 [0:(RAM_SIZE/4)-1];
+ reg [7:0] ram3 [0:(RAM_SIZE/4)-1];
+
+ // Port 1, Read only
+ always @(posedge wb_clk_i)
+ if_data[31:24] <= ram3[if_adr[AWIDTH-1:2]];
+ always @(posedge wb_clk_i)
+ if_data[23:16] <= ram2[if_adr[AWIDTH-1:2]];
+ always @(posedge wb_clk_i)
+ if_data[15:8] <= ram1[if_adr[AWIDTH-1:2]];
+ always @(posedge wb_clk_i)
+ if_data[7:0] <= ram0[if_adr[AWIDTH-1:2]];
+
+ // Port 2, R/W
+ always @(posedge wb_clk_i)
+ if(dwb_stb_i) dwb_dat_o[31:24] <= ram3[dwb_adr_i[AWIDTH-1:2]];
+ always @(posedge wb_clk_i)
+ if(dwb_stb_i) dwb_dat_o[23:16] <= ram2[dwb_adr_i[AWIDTH-1:2]];
+ always @(posedge wb_clk_i)
+ if(dwb_stb_i) dwb_dat_o[15:8] <= ram1[dwb_adr_i[AWIDTH-1:2]];
+ always @(posedge wb_clk_i)
+ if(dwb_stb_i) dwb_dat_o[7:0] <= ram0[dwb_adr_i[AWIDTH-1:2]];
+
+ always @(posedge wb_clk_i)
+ if(dwb_we_i & dwb_stb_i & dwb_sel_i[3])
+ ram3[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[31:24];
+ always @(posedge wb_clk_i)
+ if(dwb_we_i & dwb_stb_i & dwb_sel_i[2])
+ ram2[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[23:16];
+ always @(posedge wb_clk_i)
+ if(dwb_we_i & dwb_stb_i & dwb_sel_i[1])
+ ram1[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[15:8];
+ always @(posedge wb_clk_i)
+ if(dwb_we_i & dwb_stb_i & dwb_sel_i[0])
+ ram0[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[7:0];
+
+endmodule // ram_harvard