diff --git a/vhdl/backend/Altera/Firebee/firebee.qsf b/vhdl/backend/Altera/Firebee/firebee.qsf
index 989ee24..bec098e 100755
--- a/vhdl/backend/Altera/Firebee/firebee.qsf
+++ b/vhdl/backend/Altera/Firebee/firebee.qsf
@@ -689,4 +689,5 @@ set_location_assignment PIN_N7 -to IRQ_n[7]
 set_instance_assignment -name IO_STANDARD "3.0-V LVCMOS" -to IRQ_n[2]
 set_instance_assignment -name IO_STANDARD "3.0-V LVCMOS" -to IRQ_n[3]
 set_instance_assignment -name IO_STANDARD "3.0-V LVCMOS" -to IRQ_n[4]
+set_global_assignment -name FLOW_ENABLE_IO_ASSIGNMENT_ANALYSIS ON
 set_instance_assignment -name PARTITION_HIERARCHY root_partition -to | -section_id Top
\ No newline at end of file