diff --git a/src/libboard_artiq/src/cxp_downconn.rs b/src/libboard_artiq/src/cxp_downconn.rs
index b16fba9..44afac5 100644
--- a/src/libboard_artiq/src/cxp_downconn.rs
+++ b/src/libboard_artiq/src/cxp_downconn.rs
@@ -24,9 +24,9 @@ pub fn loopback_testing(channel: usize, timer: &mut GlobalTimer, speed: cxp_phys
         while (CXP[channel].downconn_rx_ready_read)() != 1 {}
         info!("rx ready!");
 
-        (CXP[channel].downconn_tx_stb_write)(1);
         cxp_proto::downconn_send_test_packet(channel);
 
+        // FIXME: why test + trig ack doesn't work well for rx??
         cxp_proto::downconn_debug_send_trig_ack(channel);
 
         const DATA_MAXSIZE: usize = 253;
@@ -51,17 +51,22 @@ pub fn loopback_testing(channel: usize, timer: &mut GlobalTimer, speed: cxp_phys
         .expect("loopback gtx tx error");
 
         timer.delay_us(1000); // wait packet has arrive at RX async fifo
-        (CXP[channel].downconn_tx_stb_write)(0);
 
-        info!("trig ack = {}", (CXP[channel].downconn_trigger_ack_read)());
-        (CXP[channel].downconn_trigger_ack_write)(1);
-        info!("after clr trig ack = {}", (CXP[channel].downconn_trigger_ack_read)());
+        if (CXP[channel].downconn_trigger_ack_read)() == 1 {
+            (CXP[channel].downconn_trigger_ack_write)(1);
+            info!("trig ack and cleared");
+        }
+
+        if (CXP[channel].downconn_bootstrap_decoder_err_read)() == 1 {
+            info!("!!!!!!!DECODER ERROR!!!!!!! and cleared");
+            (CXP[channel].downconn_bootstrap_decoder_err_write)(1);
+        }
+
+        if (CXP[channel].downconn_bootstrap_test_err_read)() == 1 {
+            info!("!!!!!!!TEST ERROR!!!!!!! and cleared");
+            (CXP[channel].downconn_bootstrap_test_err_write)(1);
+        }
 
-        info!(
-            "decoder error = {}",
-            (CXP[channel].downconn_bootstrap_decoder_err_read)()
-        );
-        info!("test error = {}", (CXP[channel].downconn_bootstrap_test_err_read)());
         info!("packet type = {:#06X}", (CXP[channel].downconn_packet_type_read)());
 
         cxp_proto::receive(channel).expect("loopback gtx rx error");
@@ -82,6 +87,8 @@ pub fn loopback_testing(channel: usize, timer: &mut GlobalTimer, speed: cxp_phys
                 break;
             }
         }
-        cxp_proto::print_packetu32(&pak_arr, &k_arr);
+
+        info!("rx ready = {}", (CXP[channel].downconn_rx_ready_read)());
+        // cxp_proto::print_packetu32(&pak_arr, &k_arr);
     }
 }