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-rw-r--r--usrp2/fpga/timing/time_64bit.v63
1 files changed, 63 insertions, 0 deletions
diff --git a/usrp2/fpga/timing/time_64bit.v b/usrp2/fpga/timing/time_64bit.v
new file mode 100644
index 000000000..c0a846e74
--- /dev/null
+++ b/usrp2/fpga/timing/time_64bit.v
@@ -0,0 +1,63 @@
+
+
+module time_64bit
+ #(parameter TICKS_PER_SEC = 32'd100000000,
+ parameter BASE = 0)
+ (input clk, input rst,
+ input set_stb, input [7:0] set_addr, input [31:0] set_data,
+ input pps,
+ output [63:0] vita_time
+ );
+
+ localparam NEXT_TICKS = 0;
+ localparam NEXT_SECS = 1;
+ localparam ROLLOVER = TICKS_PER_SEC - 1;
+
+ assign vita_time = {seconds,ticks};
+
+ wire [31:0] next_ticks_preset;
+ wire [31:0] next_seconds_preset;
+ wire set_on_pps_trig;
+ reg set_on_next_pps;
+
+ setting_reg #(.my_addr(BASE+NEXT_TICKS)) sr_next_ticks
+ (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+ .in(set_data),.out(next_ticks_preset),.changed());
+
+ setting_reg #(.my_addr(BASE+NEXT_SECS)) sr_next_secs
+ (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+ .in(set_data),.out(next_seconds_preset),.changed(set_on_pps_trig));
+
+ reg [31:0] seconds;
+ reg [31:0] ticks;
+
+ wire end_of_second;
+
+ always @(posedge clk)
+ if(rst)
+ set_on_next_pps <= 0;
+ else if(set_on_pps_trig)
+ set_on_next_pps <= 1;
+ else if(pps)
+ set_on_next_pps <= 0;
+
+ always @(posedge clk)
+ if(rst)
+ begin
+ seconds <= 32'd0;
+ ticks <= 32'd0;
+ end
+ else if(pps & set_on_next_pps)
+ begin
+ seconds <= next_seconds_preset;
+ ticks <= next_ticks_preset;
+ end
+ else if(ticks == ROLLOVER)
+ begin
+ seconds <= seconds + 1;
+ ticks <= 0;
+ end
+ else
+ ticks <= ticks + 1;
+
+endmodule // time_64bit