From 8b377a9d6d0ad281474a8dbff49ea3b093178b28 Mon Sep 17 00:00:00 2001 From: Josh Blum Date: Fri, 22 Jan 2010 16:00:45 -0800 Subject: moved into subdir --- usrp2/simple_gemac/ll8_to_txmac.v | 43 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 usrp2/simple_gemac/ll8_to_txmac.v (limited to 'usrp2/simple_gemac/ll8_to_txmac.v') diff --git a/usrp2/simple_gemac/ll8_to_txmac.v b/usrp2/simple_gemac/ll8_to_txmac.v new file mode 100644 index 000000000..3530a0c59 --- /dev/null +++ b/usrp2/simple_gemac/ll8_to_txmac.v @@ -0,0 +1,43 @@ + +module ll8_to_txmac + (input clk, input reset, input clear, + input [7:0] ll_data, input ll_sof, input ll_eof, input ll_src_rdy, output ll_dst_rdy, + output [7:0] tx_data, output tx_valid, output tx_error, input tx_ack ); + + reg [2:0] xfer_state; + + localparam XFER_IDLE = 0; + localparam XFER_ACTIVE = 1; + localparam XFER_WAIT1 = 2; + localparam XFER_UNDERRUN = 3; + localparam XFER_DROP = 4; + + always @(posedge clk) + if(reset | clear) + xfer_state <= XFER_IDLE; + else + case(xfer_state) + XFER_IDLE : + if(tx_ack) + xfer_state <= XFER_ACTIVE; + XFER_ACTIVE : + if(~ll_src_rdy) + xfer_state <= XFER_UNDERRUN; + else if(ll_eof) + xfer_state <= XFER_WAIT1; + XFER_WAIT1 : + xfer_state <= XFER_IDLE; + XFER_UNDERRUN : + xfer_state <= XFER_DROP; + XFER_DROP : + if(ll_eof) + xfer_state <= XFER_IDLE; + endcase // case (xfer_state) + + assign ll_dst_rdy = (xfer_state == XFER_ACTIVE) | tx_ack | (xfer_state == XFER_DROP); + assign tx_valid = (ll_src_rdy & (xfer_state == XFER_IDLE))|(xfer_state == XFER_ACTIVE); + assign tx_data = ll_data; + assign tx_error = (xfer_state == XFER_UNDERRUN); + +endmodule // ll8_to_txmac + -- cgit v1.2.3