diff options
| -rw-r--r-- | usrp2/udp/prot_eng_tx.v | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/usrp2/udp/prot_eng_tx.v b/usrp2/udp/prot_eng_tx.v index 3adaaa32b..0c3e58892 100644 --- a/usrp2/udp/prot_eng_tx.v +++ b/usrp2/udp/prot_eng_tx.v @@ -19,7 +19,6 @@ module prot_eng_tx // Store header values in a small dual-port (distributed) ram reg [31:0] header_ram[0:63]; - wire [31:0] header_word; reg [3:0] state; reg [1:0] port_sel; @@ -27,7 +26,14 @@ module prot_eng_tx if(set_stb & ((set_addr & 8'hC0) == BASE)) header_ram[set_addr[5:0]] <= set_data; - assign header_word = header_ram[{port_sel[1:0],state[3:0]}]; + wire [31:0] header_word = header_ram[{port_sel[1:0],state[3:0]}]; + + reg [15:0] pre_checksums [0:3]; + always @(posedge clk) + if(set_stb & (set_addr == (BASE+6))) + pre_checksums[set_addr[5:4]] <= set_data[15:0]; + + wire [15:0] pre_checksum = header_ram[port_sel[1:0]]; // Protocol State Machine reg [15:0] length; @@ -70,7 +76,7 @@ module prot_eng_tx wire [15:0] ip_checksum; add_onescomp #(.WIDTH(16)) add_onescomp - (.A(header_word[15:0]),.B(ip_length),.SUM(ip_checksum)); + (.A(pre_checksum),.B(ip_length),.SUM(ip_checksum)); reg [15:0] ip_checksum_reg; always @(posedge clk) ip_checksum_reg <= ip_checksum; |