diff --git a/fuzzers/051-imuxlout/generate.tcl b/fuzzers/051-imuxlout/generate.tcl
index 44a47cbe..9e0ea29c 100644
--- a/fuzzers/051-imuxlout/generate.tcl
+++ b/fuzzers/051-imuxlout/generate.tcl
@@ -30,7 +30,6 @@ close $fp
 set int_l_tiles [randsample_list [llength $todo_lines] [filter [pblock_tiles roi] {TYPE == INT_L}]]
 set int_r_tiles [randsample_list [llength $todo_lines] [filter [pblock_tiles roi] {TYPE == INT_R}]]
 
-set idx 0
 for {set idx 0} {$idx < [llength $todo_lines]} {incr idx} {
 	set line [lindex $todo_lines $idx]
 
diff --git a/fuzzers/053-ctrlin/.gitignore b/fuzzers/053-ctrlin/.gitignore
new file mode 100644
index 00000000..9c926485
--- /dev/null
+++ b/fuzzers/053-ctrlin/.gitignore
@@ -0,0 +1,13 @@
+/filtered_seg_int_l.segbits
+/filtered_seg_int_r.segbits
+/pattern_l.txt
+/pattern_r.txt
+/piplist.dcp
+/piplist/
+/pips_int_l.txt
+/pips_int_r.txt
+/seg_int_l.segbits
+/seg_int_r.segbits
+/specimen_[0-9][0-9][0-9]/
+/todo.txt
+/vivado*
diff --git a/fuzzers/053-ctrlin/Makefile b/fuzzers/053-ctrlin/Makefile
new file mode 100644
index 00000000..3edb4f05
--- /dev/null
+++ b/fuzzers/053-ctrlin/Makefile
@@ -0,0 +1,29 @@
+
+N := 10
+SPECIMENS := $(addprefix specimen_,$(shell seq -f '%03.0f' $(N)))
+SPECIMENS_OK := $(addsuffix /OK,$(SPECIMENS))
+
+database: $(SPECIMENS_OK)
+	${XRAY_SEGMATCH} -m 5 -M 15 -o seg_int_l.segbits $(addsuffix /segdata_clbl[lm]_l.txt,$(SPECIMENS))
+	${XRAY_SEGMATCH} -m 5 -M 15 -o seg_int_r.segbits $(addsuffix /segdata_clbl[lm]_r.txt,$(SPECIMENS))
+
+pushdb:
+	${XRAY_MERGEDB} int_l seg_int_l.segbits
+	${XRAY_MERGEDB} int_r seg_int_r.segbits
+	${XRAY_DBFIXUP}
+
+$(SPECIMENS_OK): todo.txt
+	bash generate.sh $(subst /OK,,$@)
+	touch $@
+
+todo.txt:
+	vivado -mode batch -source piplist.tcl
+	python3 maketodo.py | sort -R | head -n10 > todo.txt
+
+clean:
+	rm -rf .Xil/ .cache/ filtered_seg_int_[lr].segbits
+	rm -rf todo.txt vivado* piplist/ piplist.dcp pattern_[lr].txt pips_int_[lr].txt
+	rm -rf specimen_[0-9][0-9][0-9]/ seg_int_[lr].segbits mask_clbl[lm]_[lr].segbits
+
+.PHONY: database pushdb clean
+
diff --git a/fuzzers/053-ctrlin/generate.py b/fuzzers/053-ctrlin/generate.py
new file mode 100644
index 00000000..ff02451a
--- /dev/null
+++ b/fuzzers/053-ctrlin/generate.py
@@ -0,0 +1,72 @@
+#!/usr/bin/env python3
+
+import sys, os, re
+
+sys.path.append("../../../utils/")
+from segmaker import segmaker
+
+segmk = segmaker("design.bits")
+
+tiledata = dict()
+pipdata = dict()
+ignpip = set()
+
+print("Loading tags from design.txt.")
+with open("design.txt", "r") as f:
+    for line in f:
+        tile, pip, src, dst, pnum, pdir = line.split()
+        _, pip = pip.split(".")
+        _, src = src.split("/")
+        _, dst = dst.split("/")
+        pnum = int(pnum)
+        pdir = int(pdir)
+
+        if tile not in tiledata:
+            tiledata[tile] = {
+                "pips": set(),
+                "srcs": set(),
+                "dsts": set()
+            }
+
+        if pip in pipdata:
+            assert pipdata[pip] == (src, dst)
+        else:
+            pipdata[pip] = (src, dst)
+
+        tiledata[tile]["pips"].add(pip)
+        tiledata[tile]["srcs"].add(src)
+        tiledata[tile]["dsts"].add(dst)
+
+        if pdir == 0:
+            tiledata[tile]["srcs"].add(dst)
+            tiledata[tile]["dsts"].add(src)
+
+        if pnum == 1 or pdir == 0 or not re.match(r"^CTRL", dst):
+            ignpip.add(pip)
+
+for tile, pips_srcs_dsts in tiledata.items():
+    pips = pips_srcs_dsts["pips"]
+    srcs = pips_srcs_dsts["srcs"]
+    dsts = pips_srcs_dsts["dsts"]
+
+    for pip, src_dst in pipdata.items():
+        src, dst = src_dst
+        if pip in ignpip:
+            pass
+        elif pip in pips:
+            segmk.addtag(tile, "%s.%s" % (dst, src), 1)
+        elif src_dst[1] not in dsts:
+            segmk.addtag(tile, "%s.%s" % (dst, src), 0)
+
+def bitfilter(frame_idx, bit_idx):
+    assert os.getenv("XRAY_DATABASE") == "artix7"
+    return True
+    if frame_idx == 0 and bit_idx == 48:
+        return False
+    if frame_idx == 1 and bit_idx == 31:
+        return False
+    return frame_idx in [0, 1]
+
+segmk.compile(bitfilter=bitfilter)
+segmk.write()
+
diff --git a/fuzzers/053-ctrlin/generate.sh b/fuzzers/053-ctrlin/generate.sh
new file mode 100644
index 00000000..9f904105
--- /dev/null
+++ b/fuzzers/053-ctrlin/generate.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+source ${XRAY_GENHEADER}
+
+vivado -mode batch -source ../generate.tcl
+
+${XRAY_BITREAD} -F $XRAY_ROI_FRAMES -o design.bits -z -y design.bit
+python3 ../generate.py
+
diff --git a/fuzzers/053-ctrlin/generate.tcl b/fuzzers/053-ctrlin/generate.tcl
new file mode 100644
index 00000000..6bdaf747
--- /dev/null
+++ b/fuzzers/053-ctrlin/generate.tcl
@@ -0,0 +1,85 @@
+create_project -force -part $::env(XRAY_PART) design design
+
+read_verilog ../top.v
+synth_design -top top
+
+set_property -dict "PACKAGE_PIN $::env(XRAY_PIN_00) IOSTANDARD LVCMOS33" [get_ports i]
+set_property -dict "PACKAGE_PIN $::env(XRAY_PIN_01) IOSTANDARD LVCMOS33" [get_ports o]
+
+create_pblock roi
+resize_pblock [get_pblocks roi] -add "$::env(XRAY_ROI)"
+
+set_property CFGBVS VCCO [current_design]
+set_property CONFIG_VOLTAGE 3.3 [current_design]
+set_property BITSTREAM.GENERAL.PERFRAMECRC YES [current_design]
+
+place_design
+route_design
+
+# write_checkpoint -force design.dcp
+
+source ../../../utils/utils.tcl
+
+set fp [open "../todo.txt" r]
+set todo_lines {}
+for {gets $fp line} {$line != ""} {gets $fp line} {
+	lappend todo_lines [split $line .]
+}
+close $fp
+
+set int_l_tiles [randsample_list [llength $todo_lines] [filter [pblock_tiles roi] {TYPE == INT_L}]]
+set int_r_tiles [randsample_list [llength $todo_lines] [filter [pblock_tiles roi] {TYPE == INT_R}]]
+
+for {set idx 0} {$idx < [llength $todo_lines]} {incr idx} {
+	set line [lindex $todo_lines $idx]
+	puts "== $idx: $line"
+
+	set tile_type [lindex $line 0]
+	set dst_wire [lindex $line 1]
+	set src_wire [lindex $line 2]
+
+	if {$tile_type == "INT_L"} {set tile [lindex $int_l_tiles $idx]; set other_tile [lindex $int_r_tiles $idx]}
+	if {$tile_type == "INT_R"} {set tile [lindex $int_r_tiles $idx]; set other_tile [lindex $int_l_tiles $idx]}
+
+	set driver_site [get_sites -of_objects [get_site_pins -of_objects [get_nodes -downhill \
+			-of_objects [get_nodes -of_objects [get_wires $other_tile/CLK*0]]]]]
+
+	set recv_site [get_sites -of_objects [get_site_pins -of_objects [get_nodes -downhill \
+			-of_objects [get_nodes -of_objects [get_wires $tile/$dst_wire]]]]]
+
+	set mylut [create_cell -reference LUT1 mylut_$idx]
+	set_property -dict "LOC $driver_site BEL A6LUT" $mylut
+
+	set myff [create_cell -reference FDRE myff_$idx]
+	set ffbel [lindex "AFF A5FF BFF B5FF CFF C5FF DFF D5FF" [expr {int(rand()*8)}]]
+	set_property -dict "LOC $recv_site BEL $ffbel" $myff
+
+	set mynet [create_net mynet_$idx]
+	connect_net -net $mynet -objects "$mylut/O $myff/R"
+	route_via $mynet "$tile/$src_wire $tile/$dst_wire"
+}
+
+proc write_txtdata {filename} {
+	puts "Writing $filename."
+	set fp [open $filename w]
+	set all_pips [lsort -unique [get_pips -of_objects [get_nets -hierarchical]]]
+	if {$all_pips != {}} {
+		puts "Dumping pips."
+		foreach tile [get_tiles [regsub -all {CLBL[LM]} [get_tiles -of_objects [get_sites -of_objects [get_pblocks roi]]] INT]] {
+			foreach pip [filter $all_pips "TILE == $tile"] {
+				set src_wire [get_wires -uphill -of_objects $pip]
+				set dst_wire [get_wires -downhill -of_objects $pip]
+				set num_pips [llength [get_nodes -uphill -of_objects [get_nodes -of_objects $dst_wire]]]
+				set dir_prop [get_property IS_DIRECTIONAL $pip]
+				puts $fp "$tile $pip $src_wire $dst_wire $num_pips $dir_prop"
+			}
+		}
+	}
+	close $fp
+}
+
+route_design
+write_checkpoint -force design.dcp
+write_bitstream -force design.bit
+write_txtdata design.txt
+
diff --git a/fuzzers/053-ctrlin/maketodo.py b/fuzzers/053-ctrlin/maketodo.py
new file mode 100644
index 00000000..29c66f6f
--- /dev/null
+++ b/fuzzers/053-ctrlin/maketodo.py
@@ -0,0 +1,21 @@
+#!/usr/bin/env python3
+
+import os, re
+
+def maketodo(pipfile, dbfile):
+    todos = set()
+    with open(pipfile, "r") as f:
+        for line in f:
+            line = line.split()
+            todos.add(line[0])
+    with open(dbfile, "r") as f:
+        for line in f:
+            line = line.split()
+            todos.remove(line[0])
+    for line in todos:
+        if re.match(r"^INT_[LR].CTRL", line):
+            print(line)
+
+maketodo("pips_int_l.txt", "%s/%s/segbits_int_l.db" % (os.getenv("XRAY_DATABASE_DIR"), os.getenv("XRAY_DATABASE")))
+maketodo("pips_int_r.txt", "%s/%s/segbits_int_r.db" % (os.getenv("XRAY_DATABASE_DIR"), os.getenv("XRAY_DATABASE")))
+
diff --git a/fuzzers/053-ctrlin/piplist.tcl b/fuzzers/053-ctrlin/piplist.tcl
new file mode 100644
index 00000000..98a590a6
--- /dev/null
+++ b/fuzzers/053-ctrlin/piplist.tcl
@@ -0,0 +1,39 @@
+create_project -force -part $::env(XRAY_PART) piplist piplist
+
+read_verilog top.v
+synth_design -top top
+
+set_property -dict "PACKAGE_PIN $::env(XRAY_PIN_00) IOSTANDARD LVCMOS33" [get_ports i]
+set_property -dict "PACKAGE_PIN $::env(XRAY_PIN_01) IOSTANDARD LVCMOS33" [get_ports o]
+
+create_pblock roi
+resize_pblock [get_pblocks roi] -add "$::env(XRAY_ROI)"
+
+set_property CFGBVS VCCO [current_design]
+set_property CONFIG_VOLTAGE 3.3 [current_design]
+set_property BITSTREAM.GENERAL.PERFRAMECRC YES [current_design]
+
+place_design
+route_design
+
+write_checkpoint -force piplist.dcp
+
+source ../../utils/utils.tcl
+
+proc print_tile_pips {tile_type filename} {
+	set tile [lindex [get_tiles -filter "TYPE == $tile_type"] 0]
+	puts "Dumping and PIPs for tile $tile ($tile_type) to $filename."
+	set fp [open $filename w]
+	foreach pip [lsort [get_pips -filter {IS_DIRECTIONAL} -of_objects [get_tiles $tile]]] {
+		set src [get_wires -uphill -of_objects $pip]
+		set dst [get_wires -downhill -of_objects $pip]
+		if {[llength [get_nodes -uphill -of_objects [get_nodes -of_objects $dst]]] != 1} {
+			puts $fp "$tile_type.[regsub {.*/} $dst ""].[regsub {.*/} $src ""]"
+		}
+	}
+	close $fp
+}
+
+print_tile_pips INT_L pips_int_l.txt
+print_tile_pips INT_R pips_int_r.txt
+
diff --git a/fuzzers/053-ctrlin/top.v b/fuzzers/053-ctrlin/top.v
new file mode 100644
index 00000000..c0e91c58
--- /dev/null
+++ b/fuzzers/053-ctrlin/top.v
@@ -0,0 +1,3 @@
+module top (input i, output o);
+	assign o = i;
+endmodule