diff --git a/rtl/ethernet-udp/src/eth/mac/mac_test.v b/rtl/ethernet-udp/src/eth/mac/mac_test.v
index 1a6ad3a..f6457b3 100644
--- a/rtl/ethernet-udp/src/eth/mac/mac_test.v
+++ b/rtl/ethernet-udp/src/eth/mac/mac_test.v
@@ -4,7 +4,7 @@
 //Description :
 //
 //////////////////////////////////////////////////////////////////////////////////////
-//`define TEST_SPEED
+`define TEST_SPEED
 `timescale 1 ns/1 ns
 module mac_test
 (
@@ -74,7 +74,7 @@ parameter WAIT          = 9'b010_000_000 ;
 parameter CHECK_ARP     = 9'b100_000_000 ;
 
 
-reg [8:0]    state  ;
+(* MARK_DEBUG="true" *)  reg [8:0]    state  ;
 reg [8:0]    next_state ;
 reg  [15:0]  ram_cnt ;
 reg    almost_full_d0 ;
@@ -278,7 +278,7 @@ always@(posedge gmii_rx_clk or negedge rst_n)
 		udp_send_data_length <= udp_rec_data_length - 8  ;
 	 else
 	 `ifdef TEST_SPEED 
-       udp_send_data_length <= 16'd1000 ;	 
+       udp_send_data_length <= 16'd100 ;	 
 	 `else	 
 	   udp_send_data_length <= 4*UDP_DEPTH ;
 	 `endif
diff --git a/rtl/ethernet-udp/src/eth/util_gmii_to_rgmii.v b/rtl/ethernet-udp/src/eth/util_gmii_to_rgmii.v
index 4f457d7..4ee9163 100644
--- a/rtl/ethernet-udp/src/eth/util_gmii_to_rgmii.v
+++ b/rtl/ethernet-udp/src/eth/util_gmii_to_rgmii.v
@@ -180,7 +180,7 @@ module util_gmii_to_rgmii (
          .DELAY_SRC("IDATAIN"),           // Delay input (IDATAIN, DATAIN)
          .HIGH_PERFORMANCE_MODE("FALSE"), // Reduced jitter ("TRUE"), Reduced power ("FALSE")
          .IDELAY_TYPE("FIXED"),           // FIXED, VARIABLE, VAR_LOAD, VAR_LOAD_PIPE
-         .IDELAY_VALUE(16),                // Input delay tap setting (0-31)
+         .IDELAY_VALUE(16),                // Input delay tap setting (0-31) May be changed for more stability
          .PIPE_SEL("FALSE"),              // Select pipelined mode, FALSE, TRUE
          .REFCLK_FREQUENCY(200.0),        // IDELAYCTRL clock input frequency in MHz (190.0-210.0, 290.0-310.0).
          .SIGNAL_PATTERN("DATA")          // DATA, CLOCK input signal