diff options
Diffstat (limited to 'fpga/usrp2/fifo/fifo19_to_fifo36.v')
-rw-r--r-- | fpga/usrp2/fifo/fifo19_to_fifo36.v | 40 |
1 files changed, 23 insertions, 17 deletions
diff --git a/fpga/usrp2/fifo/fifo19_to_fifo36.v b/fpga/usrp2/fifo/fifo19_to_fifo36.v index 5f9aeff9b..0e6bcea68 100644 --- a/fpga/usrp2/fifo/fifo19_to_fifo36.v +++ b/fpga/usrp2/fifo/fifo19_to_fifo36.v @@ -1,26 +1,31 @@ +// Parameter LE tells us if we are little-endian. +// Little-endian means send lower 16 bits first. +// Default is big endian (network order), send upper bits first. + module fifo19_to_fifo36 - (input clk, input reset, input clear, - input [18:0] f19_datain, - input f19_src_rdy_i, - output f19_dst_rdy_o, + #(parameter LE=0) + (input clk, input reset, input clear, + input [18:0] f19_datain, + input f19_src_rdy_i, + output f19_dst_rdy_o, - output [35:0] f36_dataout, - output f36_src_rdy_o, - input f36_dst_rdy_i, - output [31:0] debug - ); + output [35:0] f36_dataout, + output f36_src_rdy_o, + input f36_dst_rdy_i, + output [31:0] debug + ); - reg f36_sof, f36_eof, f36_occ; + reg f36_sof, f36_eof, f36_occ; - reg [1:0] state; - reg [15:0] dat0, dat1; + reg [1:0] state; + reg [15:0] dat0, dat1; - wire f19_sof = f19_datain[16]; - wire f19_eof = f19_datain[17]; - wire f19_occ = f19_datain[18]; + wire f19_sof = f19_datain[16]; + wire f19_eof = f19_datain[17]; + wire f19_occ = f19_datain[18]; - wire xfer_out = f36_src_rdy_o & f36_dst_rdy_i; + wire xfer_out = f36_src_rdy_o & f36_dst_rdy_i; always @(posedge clk) if(f19_src_rdy_i & ((state==0)|xfer_out)) @@ -68,7 +73,8 @@ module fifo19_to_fifo36 dat0 <= f19_datain; assign f19_dst_rdy_o = xfer_out | (state != 2); - assign f36_dataout = {f36_occ,f36_eof,f36_sof,dat0,dat1}; + assign f36_dataout = LE ? {f36_occ,f36_eof,f36_sof,dat1,dat0} : + {f36_occ,f36_eof,f36_sof,dat0,dat1}; assign f36_src_rdy_o = (state == 2); assign debug = state; |