[Commit-gnuradio] r9103 - usrp2/trunk/fpga/serdes

[matt]

Author: matt
Date: 2008-07-31 20:33:30 -0600 (Thu, 31 Jul 2008)
New Revision: 9103

Modified:
   usrp2/trunk/fpga/serdes/serdes_fc_tx.v
Log:
removed clock domain crossing since that is now done in the receiver


Modified: usrp2/trunk/fpga/serdes/serdes_fc_tx.v
===================================================================
--- usrp2/trunk/fpga/serdes/serdes_fc_tx.v      2008-08-01 02:32:47 UTC (rev 
9102)
+++ usrp2/trunk/fpga/serdes/serdes_fc_tx.v      2008-08-01 02:33:30 UTC (rev 
9103)
@@ -2,38 +2,18 @@
 
 module serdes_fc_tx
   (input clk, input rst,
-   input ser_rx_clk, input xon_rcvd, input xoff_rcvd, output reg inhibit_tx);
+   input xon_rcvd, input xoff_rcvd, output reg inhibit_tx);
 
    // XOFF means stop sending, XON means start sending
-   
-   reg          xon_d1, xon_d2, xoff_d1, xoff_d2;
-   reg          xon_ret, xon_ret_d1, xoff_ret, xoff_ret_d1;
+   // clock domain stuff happens elsewhere, everything here is on main clk
 
-   // Make delayed copies in its own clock domain
-   always @(posedge ser_rx_clk)
-     begin
-       xon_d1 <= xon_rcvd;
-       xon_d2 <= xon_d1;
-       xoff_d1 <= xoff_rcvd;
-       xoff_d2 <= xoff_d1;
-     end
-
-   // Transfer copies to our clock domain, flop once for metastability purposes
-   always @(posedge clk)
-     begin
-       xon_ret <= xon_rcvd | xon_d1 | xon_d2;
-       xoff_ret <= xoff_rcvd | xoff_d1 | xoff_d2;
-       xon_ret_d1 <= xon_ret;
-       xoff_ret_d1 <= xoff_ret;
-     end
-   
    reg [15:0] state;
    always @(posedge clk)
      if(rst)
        state <= 0;
-     else if(xoff_ret_d1)
+     else if(xoff_rcvd)
        state <= 255;
-     else if(xon_ret_d1)
+     else if(xon_rcvd)
        state <= 0;
      else if(state !=0)
        state <= state - 1;