1 files changed, 98 insertions, 0 deletions
diff --git a/fpga/usrp2/vrt/vita_tx_control.v b/fpga/usrp2/vrt/vita_tx_control.v
new file mode 100644
index 000000000..bffc64e52
--- /dev/null
+++ b/fpga/usrp2/vrt/vita_tx_control.v
@@ -0,0 +1,98 @@
+
+module vita_tx_control
+  #(parameter BASE=0,
+    parameter WIDTH=32)
+   (input clk, input reset, input clear,
+    input set_stb, input [7:0] set_addr, input [31:0] set_data,
+    
+    input [63:0] vita_time,
+    output underrun,
+
+    // From vita_tx_deframer
+    input [4+64+WIDTH-1:0] sample_fifo_i,
+    input sample_fifo_src_rdy_i,
+    output sample_fifo_dst_rdy_o,
+    
+    // To DSP Core
+    output [WIDTH-1:0] sample,
+    output run,
+    input strobe,
+
+    output [31:0] debug
+    );
+   
+   assign sample = sample_fifo_i[4+64+WIDTH-1:4+64];
+
+   wire [63:0] send_time = sample_fifo_i[63:0];
+   wire        eop = sample_fifo_i[64];
+   wire        eob = sample_fifo_i[65];
+   wire        sob = sample_fifo_i[66];
+   wire        send_at = sample_fifo_i[67];
+   wire        now, early, late, too_early;
+
+   // FIXME ignore too_early for now for timing reasons
+   assign too_early = 0;
+   time_compare 
+     time_compare (.time_now(vita_time), .trigger_time(send_time), .now(now), .early(early), 
+		   .late(late), .too_early());
+//		   .late(late), .too_early(too_early));
+   
+   localparam IBS_IDLE = 0;
+   localparam IBS_RUN = 1;  // FIXME do we need this?
+   localparam IBS_CONT_BURST = 2;
+   localparam IBS_UNDERRUN = 3;
+   localparam IBS_UNDERRUN_DONE = 4;
+   
+   reg [2:0] ibs_state;
+
+   wire      clear_state;
+   setting_reg #(.my_addr(BASE+1)) sr
+     (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr),
+      .in(set_data),.out(),.changed(clear_state));
+   
+   always @(posedge clk)
+     if(reset | clear_state)
+       ibs_state <= 0;
+     else
+       case(ibs_state)
+	 IBS_IDLE :
+	   if(sample_fifo_src_rdy_i)
+	     if(~send_at | now)
+	       ibs_state <= IBS_RUN;
+	     else if(late | too_early)
+	       ibs_state <= IBS_UNDERRUN;
+	 
+	 IBS_RUN :
+	   if(strobe)
+	     if(~sample_fifo_src_rdy_i)
+	       ibs_state <= IBS_UNDERRUN;
+	     else if(eop)
+	       if(eob)
+		 ibs_state <= IBS_IDLE;
+	       else
+		 ibs_state <= IBS_CONT_BURST;
+
+	 IBS_CONT_BURST :
+	   if(strobe)
+	     ibs_state <= IBS_UNDERRUN_DONE;
+	   else if(sample_fifo_src_rdy_i)
+	     ibs_state <= IBS_RUN;
+	 
+	 IBS_UNDERRUN :
+	   if(sample_fifo_src_rdy_i & eop)
+	     ibs_state <= IBS_UNDERRUN_DONE;
+
+	 IBS_UNDERRUN_DONE :
+	   ;
+       endcase // case (ibs_state)
+
+   assign sample_fifo_dst_rdy_o = (ibs_state == IBS_UNDERRUN) | (strobe & (ibs_state == IBS_RUN));  // FIXME also cleanout
+   assign run = (ibs_state == IBS_RUN) | (ibs_state == IBS_CONT_BURST);
+   assign underrun = (ibs_state == IBS_UNDERRUN_DONE);
+
+   assign debug = { { now,early,late,too_early,eop,eob,sob,send_at },
+		    { sample_fifo_src_rdy_i, sample_fifo_dst_rdy_o, strobe, run, underrun, ibs_state[2:0] },
+		    { 8'b0 },
+		    { 8'b0 } };
+   
+endmodule // vita_tx_control