diff options
Diffstat (limited to 'fpga/usrp3/lib/control/settings_bus_crossclock.v')
-rw-r--r-- | fpga/usrp3/lib/control/settings_bus_crossclock.v | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/fpga/usrp3/lib/control/settings_bus_crossclock.v b/fpga/usrp3/lib/control/settings_bus_crossclock.v new file mode 100644 index 000000000..2a6e7e7ef --- /dev/null +++ b/fpga/usrp3/lib/control/settings_bus_crossclock.v @@ -0,0 +1,26 @@ +// +// Copyright 2011-2012 Ettus Research LLC +// + + + + +// This module takes the settings bus on one clock domain and crosses it over to another domain +// Typically it will be used with the input settings bus on the wishbone clock, and either +// the system or dsp clock on the output side + +module settings_bus_crossclock + #(parameter FLOW_CTRL=0, parameter AWIDTH=8, parameter DWIDTH=32) + (input clk_i, input rst_i, input set_stb_i, input [AWIDTH-1:0] set_addr_i, input [DWIDTH-1:0] set_data_i, + input clk_o, input rst_o, output set_stb_o, output [AWIDTH-1:0] set_addr_o, output [DWIDTH-1:0] set_data_o, input blocked); + + wire nfull, nempty; + + axi_fifo_2clk #(.WIDTH(AWIDTH + DWIDTH), .SIZE(0)) settings_fifo + (.reset(rst_i), + .i_aclk(clk_i), .i_tdata({set_addr_i,set_data_i}), .i_tvalid(set_stb_i), .i_tready(nfull), + .o_aclk(clk_o), .o_tdata({set_addr_o,set_data_o}), .o_tready(set_stb_o), .o_tvalid(nempty)); + + assign set_stb_o = nempty & (~blocked | ~FLOW_CTRL); + +endmodule // settings_bus_crossclock |