diff options
Diffstat (limited to 'usrp2/timing/time_sender.v')
-rw-r--r-- | usrp2/timing/time_sender.v | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/usrp2/timing/time_sender.v b/usrp2/timing/time_sender.v new file mode 100644 index 000000000..aa2fcbbdb --- /dev/null +++ b/usrp2/timing/time_sender.v @@ -0,0 +1,110 @@ + + +module time_sender + (input clk, input rst, + input [31:0] master_time, + input send_sync, + output exp_pps_out); + + reg [7:0] datain; + reg k; + wire [9:0] dataout; + reg [9:0] dataout_reg; + reg disp_reg; + wire disp, new_word; + + encode_8b10b encode_8b10b + (.datain({k,datain}),.dispin(disp_reg), + .dataout(dataout),.dispout(disp)); + + assign exp_pps_out = dataout_reg[0]; + + 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]}; + + reg [4:0] state; + reg [3:0] bit_count; + + 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 COMMA = 8'hBC; + localparam HEAD = 8'h3C; + + reg [31:0] master_time_reg; + + always @(posedge clk) + if(rst) + master_time_reg <= 0; + else if(send_sync) + master_time_reg <= master_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, master_time_reg[31:24] }; + state <= SEND_T1; + end + SEND_T1 : + begin + {k,datain} <= {1'b0, master_time_reg[23:16]}; + state <= SEND_T2; + end + SEND_T2 : + begin + {k,datain} <= {1'b0, master_time_reg[15:8]}; + state <= SEND_T3; + end + SEND_T3 : + begin + {k,datain} <= {1'b0, master_time_reg[7:0]}; + state <= SEND_IDLE; + end + default : + state <= SEND_IDLE; + endcase // case(state) + + +endmodule // time_sender |