Only check high 32 bits stability before accepting latch data if in MBLT mode.

src/vme_data_bus.vhd

@@ -590,8 +590,10 @@ begin
           -- Howver, according to observation 2.47a, then data is
           -- valid WITHIN 25ns. 
           if (n_wait = 0) then
-            -- Latched data stable
-            if (cur_data = l_data_r) then
+            -- Latched data stable; only check used bits
+            if (cur_data(31 downto 0) = l_data_r(31 downto 0) and
+                (transfer_mode /= MBLT or
+                 cur_data(63 downto 32) = l_data_r(63 downto 32))) then
               -- Slave only maintains data lines while
               -- DS* asserted. They can be deasserted now. 
               vme_ds_n_o <= "11";