diff --git a/src/libboard_artiq/src/cxp_upconn.rs b/src/libboard_artiq/src/cxp_upconn.rs
index b87a160..f7158ac 100644
--- a/src/libboard_artiq/src/cxp_upconn.rs
+++ b/src/libboard_artiq/src/cxp_upconn.rs
@@ -53,65 +53,87 @@ pub fn tx_test(timer: &mut GlobalTimer) {
     const D01_1: u16 = 0x21;
     const D31_1: u16 = 0x3F;
 
-    const LEN: usize = 200;
-    let mut arr: [u16; LEN] = [0; LEN];
+    const LEN: usize = 4 * 100;
+    let mut pak_arr: [u8; LEN] = [0; LEN];
 
     unsafe {
-        csr::cxp::upconn_clk_reset_write(1);
-        // csr::cxp::upconn_bitrate2x_enable_write(1);
-        csr::cxp::upconn_clk_reset_write(0);
-
         loop {
+            csr::cxp::upconn_clk_reset_write(1);
+            // csr::cxp::upconn_bitrate2x_enable_write(1);
+            csr::cxp::upconn_clk_reset_write(0);
+
             // TODO: verify the char & word boundary thingy
             for _ in 0..12 {
                 csr::cxp::upconn_symbol2_write(D31_1);
             }
 
             csr::cxp::upconn_tx_enable_write(1);
-            // timer.delay_us(1);
+            timer.delay_us(1);
 
             for _ in 0..3 {
                 csr::cxp::upconn_symbol0_write(D01_1);
             }
+            timer.delay_us(10);
 
-            for i in 0..LEN {
-                arr[i] = get_encoded();
-                // if csr::cxp::upconn_tx_busy_read() == 0 {
-                //     break;
-                // };
-            }
-            let mut last_encoded: u16 = 0;
-            for i in 0..LEN {
-                if last_encoded != arr[i] {
-                    match arr[i] {
-                        0b1010111001 | 0b0101001001 => {
-                            println!("D31.1")
-                        }
-                        0b0111011001 | 0b1000101001 => {
-                            println!("D01.1")
-                        }
-                        0b1101010010 | 0b0010101101 => {
-                            println!("D04.4")
-                        }
-                        0b0011111010 | 0b1100000101 => {
-                            println!("K28.5 start idling...")
-                        }
-                        0b0011111001 | 0b1100000110 => {
-                            println!("K28.1 idling...")
-                        }
-                        0b1010101010 => {
-                            println!("D21.5 END idle")
-                        }
-                        _ => {
-                            println!("encoded = {:#012b}", arr[i])
-                        }
-                    }
-                    last_encoded = arr[i]
+            let mut i: usize = 0;
+            while csr::cxp::upconn_upconn_phy_debug_buf_dout_valid_read() == 1 {
+                pak_arr[i] = csr::cxp::upconn_upconn_phy_debug_buf_dout_pak_read();
+                // println!("received {:#04X}", pak_arr[i]);
+                csr::cxp::upconn_upconn_phy_debug_buf_inc_write(1);
+                i += 1;
+                if i == LEN {
+                    break;
                 }
             }
-            println!("-------------------------------------");
 
-            csr::cxp::upconn_tx_enable_write(0);
+            println!("arr = [");
+            for i in 0..(LEN / 4) {
+                println!(
+                    "     {:#04X} {:#04X} {:#04X} {:#04X},",
+                    pak_arr[i * 4],
+                    pak_arr[i * 4 + 1],
+                    pak_arr[i * 4 + 2],
+                    pak_arr[i * 4 + 3]
+                )
+            }
+            println!("]");
+            // for i in 0..LEN {
+            //     arr[i] = get_encoded();
+            //     // if csr::cxp::upconn_tx_busy_read() == 0 {
+            //     //     break;
+            //     // };
+            // }
+            // let mut last_encoded: u16 = 0;
+            // for i in 0..LEN {
+            //     if last_encoded != arr[i] {
+            //         match arr[i] {
+            //             0b1010111001 | 0b0101001001 => {
+            //                 println!("D31.1")
+            //             }
+            //             0b0111011001 | 0b1000101001 => {
+            //                 println!("D01.1")
+            //             }
+            //             0b1101010010 | 0b0010101101 => {
+            //                 println!("D04.4")
+            //             }
+            //             0b0011111010 | 0b1100000101 => {
+            //                 println!("K28.5 start idling...")
+            //             }
+            //             0b0011111001 | 0b1100000110 => {
+            //                 println!("K28.1 idling...")
+            //             }
+            //             0b1010101010 => {
+            //                 println!("D21.5 END idle")
+            //             }
+            //             _ => {
+            //                 println!("encoded = {:#012b}", arr[i])
+            //             }
+            //         }
+            //         last_encoded = arr[i]
+            //     }
+            // }
+            // println!("-------------------------------------");
+
             timer.delay_us(2_000_000);
         }
     }