diff --git a/sniffer_hex.py b/sniffer_hex.py
new file mode 100644
index 0000000..f5be396
--- /dev/null
+++ b/sniffer_hex.py
@@ -0,0 +1,54 @@
+#-------------------------------------------------------------------------------
+# simulator
+# 05/07/2022
+# tool script to print everything seen on a serial link as hex with a timestamp
+#
+# usage ex: python sniffer_hex
+#-------------------------------------------------------------------------------
+
+import serial
+import sys
+import time
+
+ports = {"obs1": "/dev/ttyS20"}
+
+def main():
+
+    port = ports["obs1"]
+    speed = 9600
+
+    # parse argv
+    args = sys.argv
+    if len(args) == 1:
+        pass
+    elif len(args) == 2:
+        if args[1] in ports:
+            port = ports[args[1]]
+        else:
+            print("unknown port")
+            return 1
+    elif len(args) == 3:
+        speed = int(args[1])
+    else:
+        print("too many arguments")
+        return 1
+
+    # open serial and identify board
+    ser = serial.Serial(port, speed, timeout=0.1)
+    print("openned port", ser.name)
+    while (True):
+      raw_msg = ser.read(size=100)
+      if len(raw_msg) != 0:
+        print(timestamp() + raw_msg.hex())
+    return 0
+
+def timestamp():
+  timestamp = time.strftime("[%H:%M:%S.", time.localtime())
+  timestamp += str(int((time.time_ns() / 1e6) % 1000)).rjust(3, '0')
+  timestamp += "] "
+  return timestamp
+
+
+if __name__ == "__main__":
+    main()
+