diff --git a/fuzzers/030-iob/Makefile b/fuzzers/030-iob/Makefile
index a3533751..2867ac12 100644
--- a/fuzzers/030-iob/Makefile
+++ b/fuzzers/030-iob/Makefile
@@ -6,7 +6,7 @@ database: build/segbits_xiob33.db
 
 build/iobanks.txt: write_io_banks.tcl
 	mkdir -p build
-	cd build/ && ${XRAY_VIVADO} -mode batch -source ${FUZDIR}/write_io_banks.tcl
+	cd build/ && ${XRAY_VIVADO} -mode batch -source ../write_io_banks.tcl
 
 build/segbits_xiob33.rdb: $(SPECIMENS_OK)
 	${XRAY_SEGMATCH} -c 12 -o build/segbits_xiob33.rdb $$(find -name segdata_liob33.txt) $$(find -name segdata_riob33.txt)
diff --git a/fuzzers/030-iob/write_io_banks.tcl b/fuzzers/030-iob/write_io_banks.tcl
new file mode 100644
index 00000000..996928e7
--- /dev/null
+++ b/fuzzers/030-iob/write_io_banks.tcl
@@ -0,0 +1,8 @@
+create_project -force -part $::env(XRAY_PART) design design
+set_property design_mode PinPlanning [current_fileset]
+open_io_design -name io_1
+set fp [open "iobanks.txt" "w"]
+foreach iobank [get_iobanks] {
+    puts $fp $iobank
+}
+close $fp