Updated comment.

libraries/base/dp/tb/vhdl/tb_dp_bsn_sync_scheduler.vhd

@@ -63,6 +63,10 @@
 --    temporarily changing the ASSERT condition
 --  b Initialy used LOOP in p_stimuli to repeat test. Later used list of
 --    c_nof_test_intervals and tb_state to try different stimuli.
+--
+-- References:
+-- [1] https://support.astron.nl/confluence/pages/viewpage.action?spaceKey=L2M&title=L2+STAT+Decision%3A+Timing+in+Station
+--
 
 LIBRARY IEEE, common_lib, dp_lib;
 USE IEEE.STD_LOGIC_1164.ALL;
@@ -516,17 +520,17 @@ BEGIN
   -----------------------------------------------------------------------------
   verify_sync <= NOT recover_from_in_lost;
 
-  proc_dp_verify_sync(TO_UINT(ctrl_start_bsn),
-                              ctrl_interval_size,
-                              g_block_size,
-                              clk,
-                              verify_sync,
-                              out_sosi.sync,
-                              out_sosi.sop,
-                              out_sosi.bsn,
-                              dbg_nof_blk,
-                              dbg_accumulate,
-                              dbg_expected_bsn);
+  -- Verify that sync is on PPS and BSN grid as defined in [1].
+  proc_dp_verify_sync(ctrl_interval_size,
+                      g_block_size,
+                      clk,
+                      verify_sync,
+                      out_sosi.sync,
+                      out_sosi.sop,
+                      out_sosi.bsn,
+                      dbg_nof_blk,
+                      dbg_accumulate,
+                      dbg_expected_bsn);
 
   dbg_out_sosi_sync <= out_sosi.sync;
   dbg_out_sosi_sop  <= out_sosi.sop;