diff --git a/tools_python/pr.py b/tools_python/pr.py
index b4a9bf7..0f8e1f2 100644
--- a/tools_python/pr.py
+++ b/tools_python/pr.py
@@ -2,12 +2,11 @@
 # 2018 furrtek - furrtek.org
 # See LICENSE
 
-def terminate_frame(frame, repeats):
-    # Compute whole frame's CRC16
+def crc16(data):
     result = 0x8408
     poly = 0x8408
 
-    for by in frame:
+    for by in data:
         result ^= by
         for bi in range(0, 8):
             if (result & 1):
@@ -16,8 +15,12 @@ def terminate_frame(frame, repeats):
             else:
                 result >>= 1
 
-    frame.append(result & 255)
-    frame.append((result // 256) & 255)
+    return result
+
+def terminate_frame(frame, repeats):
+    crc = crc16(frame)
+    frame.append(crc & 255)
+    frame.append((crc // 256) & 255)
     frame.append(repeats & 255)             # This is used by the transmitter, it's not part of the transmitted data
     frame.append((repeats // 256) & 255)    # This is used by the transmitter, it's not part of the transmitted data
 
diff --git a/tools_python/setsegs.py b/tools_python/setsegs.py
new file mode 100644
index 0000000..0720fb5
--- /dev/null
+++ b/tools_python/setsegs.py
@@ -0,0 +1,68 @@
+# Allows setting ESL segments
+# 2019 furrtek - furrtek.org
+# See LICENSE
+
+import pr
+import tx
+import sys
+
+def usage():
+    print("Usage:")
+    print("setsegs.py port barcode bitmap\n")
+    print("  port: serial port name (0 for ESL Blaster)")
+    print("  barcode: 17-character barcode data, or 0")
+    print("  bitmap: hex 23-byte segment on/off bitmap")
+    exit()
+
+if len(sys.argv) != 4:
+    usage()
+if len(sys.argv[3]) != 46:
+    print("Segment bitmap must be exactly 46 digits")
+    usage()
+
+port = sys.argv[1]
+
+# Search for connected ESL Blaster if required
+if (port == "0"):
+    blaster_port = tx.search_esl_blaster()
+    if (blaster_port == "0"):
+        exit()
+
+# Get PLID from barcode string
+PLID = pr.get_plid(sys.argv[2])
+
+bitmap = bytearray.fromhex(sys.argv[3])
+
+frames = []
+
+# Update page command + data
+payload = [0xBA, 0x00, 0x00, 0x00]
+payload.extend(bitmap[1:])
+# Segment bitmap has its own CRC16
+segcrc = pr.crc16(bitmap)
+payload.append(segcrc & 255)
+payload.append((segcrc // 256) & 255)
+# Page number, duration and some other unknown stuff
+payload.extend([0x00, 0x00, 0x09, 0x00, 0x10, 0x00, 0x31])
+
+frame = pr.make_raw_frame(0x84, PLID, payload[0])
+frame.extend(payload[1:])
+pr.terminate_frame(frame, 100)
+frames.append(frame)
+
+print(frame)
+
+# DEBUG
+#f = open("out.txt", "w")
+#for fr in frames:
+#    for b in fr:
+#        f.write(format(b, '02X') + " ")
+#    f.write("\n")
+#exit()
+
+# Send data to IR transmitter
+if (port == "0"):
+    tx.transmit_esl_blaster(frames, blaster_port)
+else:
+    tx.transmit_serial(frames, port)
+print("Done.")
diff --git a/tools_python/tx.py b/tools_python/tx.py
index fb85a39..5ceeb98 100644
--- a/tools_python/tx.py
+++ b/tools_python/tx.py
@@ -21,7 +21,7 @@ def search_esl_blaster():
             else:
                 print("Timeout on " + comport)
         except serial.SerialException:
-            print("SerialException on " + comport)
+            #print("SerialException on " + comport)
             continue
 
     if (found == 0):