diff options
Diffstat (limited to 'usrp2')
-rw-r--r-- | usrp2/fpga/timing/time_64bit.v | 63 |
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 |