diff options
Diffstat (limited to 'fpga/usrp2/fifo/crossbar36.v')
-rw-r--r-- | fpga/usrp2/fifo/crossbar36.v | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/fpga/usrp2/fifo/crossbar36.v b/fpga/usrp2/fifo/crossbar36.v new file mode 100644 index 000000000..2a046d8bf --- /dev/null +++ b/fpga/usrp2/fifo/crossbar36.v @@ -0,0 +1,42 @@ + + +module crossbar36 + (input clk, input reset, input clear, + input cross, + input [35:0] data0_i, input src0_rdy_i, output dst0_rdy_o, + input [35:0] data1_i, input src1_rdy_i, output dst1_rdy_o, + output [35:0] data0_o, output src0_rdy_o, input dst0_rdy_i, + output [35:0] data1_o, output src1_rdy_o, input dst1_rdy_i); + + reg cross_int, active0, active1; + wire active0_next = (src0_rdy_i & dst0_rdy_o)? ~data0_i[33] : active0; + wire active1_next = (src1_rdy_i & dst1_rdy_o)? ~data1_i[33] : active1; + + assign data0_o = cross_int ? data1_i : data0_i; + assign data1_o = cross_int ? data0_i : data1_i; + + assign src0_rdy_o = cross_int ? src1_rdy_i : src0_rdy_i; + assign src1_rdy_o = cross_int ? src0_rdy_i : src1_rdy_i; + + assign dst0_rdy_o = cross_int ? dst1_rdy_i : dst0_rdy_i; + assign dst1_rdy_o = cross_int ? dst0_rdy_i : dst1_rdy_i; + + always @(posedge clk) + if(reset | clear) + active0 <= 0; + else + active0 <= active0_next; + + always @(posedge clk) + if(reset | clear) + active1 <= 0; + else + active1 <= active1_next; + + always @(posedge clk) + if(reset | clear) + cross_int <= 0; + else if(~active0_next & ~active1_next) + cross_int <= cross; + +endmodule // crossbar36 |