diff options
Diffstat (limited to 'fpga/usrp2/timing/time_sender.v')
-rw-r--r-- | fpga/usrp2/timing/time_sender.v | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/fpga/usrp2/timing/time_sender.v b/fpga/usrp2/timing/time_sender.v new file mode 100644 index 000000000..fdf6b1240 --- /dev/null +++ b/fpga/usrp2/timing/time_sender.v @@ -0,0 +1,157 @@ +// +// 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/>. +// + + + +module time_sender + (input clk, input rst, + input [63:0] vita_time, + input send_sync, + output reg exp_time_out); + + reg [7:0] datain; + reg k; + wire [9:0] dataout; + reg [9:0] dataout_reg; + reg disp_reg; + wire disp, new_word; + reg [4:0] state; + reg [3:0] bit_count; + + encode_8b10b encode_8b10b + (.datain({k,datain}),.dispin(disp_reg), + .dataout(dataout),.dispout(disp)); + + always @(posedge clk) + if(rst) + disp_reg <= 0; + else if(new_word) + disp_reg <= disp; + + always @(posedge clk) + if(rst) + dataout_reg <= 0; + else if(new_word) + dataout_reg <= dataout; + else + dataout_reg <= {1'b0,dataout_reg[9:1]}; + + always @(posedge clk) + exp_time_out <= dataout_reg[0]; + + assign new_word = (bit_count == 9); + + always @(posedge clk) + if(rst) + bit_count <= 0; + else if(new_word | send_sync) + bit_count <= 0; + else + bit_count <= bit_count + 1; + + localparam SEND_IDLE = 0; + localparam SEND_HEAD = 1; + localparam SEND_T0 = 2; + localparam SEND_T1 = 3; + localparam SEND_T2 = 4; + localparam SEND_T3 = 5; + localparam SEND_T4 = 6; + localparam SEND_T5 = 7; + localparam SEND_T6 = 8; + localparam SEND_T7 = 9; + localparam SEND_TAIL = 10; + + localparam COMMA = 8'hBC; + localparam HEAD = 8'h3C; + localparam TAIL = 8'hF7; + + reg [63:0] vita_time_reg; + + always @(posedge clk) + if(rst) + vita_time_reg <= 0; + else if(send_sync) + vita_time_reg <= vita_time; + + always @(posedge clk) + if(rst) + begin + {k,datain} <= 0; + state <= SEND_IDLE; + end + else + if(send_sync) + state <= SEND_HEAD; + else if(new_word) + case(state) + SEND_IDLE : + {k,datain} <= {1'b1,COMMA}; + SEND_HEAD : + begin + {k,datain} <= {1'b1, HEAD}; + state <= SEND_T0; + end + SEND_T0 : + begin + {k,datain} <= {1'b0, vita_time_reg[63:56] }; + state <= SEND_T1; + end + SEND_T1 : + begin + {k,datain} <= {1'b0, vita_time_reg[55:48]}; + state <= SEND_T2; + end + SEND_T2 : + begin + {k,datain} <= {1'b0, vita_time_reg[47:40]}; + state <= SEND_T3; + end + SEND_T3 : + begin + {k,datain} <= {1'b0, vita_time_reg[39:32]}; + state <= SEND_T4; + end + SEND_T4 : + begin + {k,datain} <= {1'b0, vita_time_reg[31:24]}; + state <= SEND_T5; + end + SEND_T5 : + begin + {k,datain} <= {1'b0, vita_time_reg[23:16]}; + state <= SEND_T6; + end + SEND_T6 : + begin + {k,datain} <= {1'b0, vita_time_reg[15:8]}; + state <= SEND_T7; + end + SEND_T7 : + begin + {k,datain} <= {1'b0, vita_time_reg[7:0]}; + state <= SEND_TAIL; + end + SEND_TAIL : + begin + {k,datain} <= {1'b1, TAIL}; + state <= SEND_IDLE; + end + default : + state <= SEND_IDLE; + endcase // case(state) + +endmodule // time_sender |