--- /dev/null
+#!/usr/bin/env python
+# Script that can read from a serial device and show timestamps.
+#
+# Copyright (C) 2009 Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+# Usage:
+# tools/readserial.py /dev/ttyUSB0 115200
+
+import sys
+import time
+import select
+import optparse
+
+# Reset time counter after this much idle time.
+RESTARTINTERVAL = 60
+# Number of bits in a transmitted byte - 8N1 is 1 start bit + 8 data
+# bits + 1 stop bit.
+BITSPERBYTE = 10
+
+def calibrateserialwrite(outfile, byteadjust):
+ # Build 4000 bytes of dummy data.
+ data = "0123456789" * 4 + "012345678" + "\n"
+ data = data * 80
+ while 1:
+ st = time.time()
+ outfile.write(data)
+ outfile.flush()
+ et = time.time()
+ sys.stdout.write(
+ "Wrote %d - %.1fus per char (theory states %.1fus)\n" % (
+ len(data), (et-st) / len(data) * 1000000, byteadjust * 1000000))
+ sys.stdout.flush()
+ time.sleep(3)
+
+def calibrateserialread(infile, byteadjust):
+ starttime = lasttime = 0
+ totalchars = 0
+ while 1:
+ select.select([infile], [], [])
+ d = infile.read(4096)
+ curtime = time.time()
+ if curtime - lasttime > 1.0:
+ if starttime and totalchars:
+ sys.stdout.write(
+ "Calibrating on %d bytes - %.1fus per char"
+ " (theory states %.1fus)\n" % (
+ totalchars,
+ float(lasttime - starttime) * 1000000 / totalchars,
+ byteadjust * 1000000))
+ totalchars = 0
+ starttime = curtime
+ else:
+ totalchars += len(d)
+ lasttime = curtime
+
+def readserial(infile, logfile, byteadjust):
+ lasttime = 0
+ while 1:
+ # Read data
+ try:
+ res = select.select([infile, sys.stdin], [], [])
+ except KeyboardInterrupt:
+ sys.stdout.write("\n")
+ break
+ if sys.stdin in res[0]:
+ # Got keyboard input - force reset on next serial input
+ sys.stdin.read(1)
+ lasttime = 0
+ if len(res[0]) == 1:
+ continue
+ d = infile.read(4096)
+ if not d:
+ break
+ datatime = time.time()
+
+ datatime -= len(d) * byteadjust
+
+ # Reset start time if no data for some time
+ if datatime - lasttime > RESTARTINTERVAL:
+ starttime = datatime
+ charcount = 0
+ isnewline = 1
+ msg = "\n\n======= %s (adjust=%.1fus)\n" % (
+ time.asctime(time.localtime(datatime)), byteadjust * 1000000)
+ sys.stdout.write(msg)
+ logfile.write(msg)
+ lasttime = datatime
+
+ # Translate unprintable chars; add timestamps
+ out = ""
+ for c in d:
+ if isnewline:
+ delta = datatime - starttime - (charcount * byteadjust)
+ out += "%06.3f: " % delta
+ isnewline = 0
+ oc = ord(c)
+ charcount += 1
+ datatime += byteadjust
+ if oc == 0x0d:
+ continue
+ if oc == 0x00:
+ out += "<00>\n"
+ isnewline = 1
+ continue
+ if oc == 0x0a:
+ out += "\n"
+ isnewline = 1
+ continue
+ if oc < 0x20 or oc >= 0x7f and oc != 0x09:
+ out += "<%02x>" % oc
+ continue
+ out += c
+
+ sys.stdout.write(out)
+ sys.stdout.flush()
+ logfile.write(out)
+ logfile.flush()
+
+def main():
+ usage = "%prog [options] [<serialdevice> [<baud>]]"
+ opts = optparse.OptionParser(usage)
+ opts.add_option("-f", "--file",
+ action="store_false", dest="serial", default=True,
+ help="read from file instead of serialdevice")
+ opts.add_option("-n", "--no-adjust",
+ action="store_false", dest="adjustbaud", default=True,
+ help="don't adjust times by serial rate")
+ opts.add_option("-c", "--calibrate-read",
+ action="store_true", dest="calibrate_read", default=False,
+ help="read from serial port to calibrate it")
+ opts.add_option("-C", "--calibrate-write",
+ action="store_true", dest="calibrate_write", default=False,
+ help="write to serial port to calibrate it")
+ opts.add_option("-t", "--time",
+ type="float", dest="time", default=None,
+ help="time to write one byte on serial port (in us)")
+ options, args = opts.parse_args()
+ serialport = 0
+ baud = 115200
+ if len(args) > 2:
+ opts.error("Too many arguments")
+ if len(args) > 0:
+ serialport = args[0]
+ if len(args) > 1:
+ baud = int(args[1])
+ byteadjust = float(BITSPERBYTE) / baud
+ if options.time is not None:
+ byteadjust = options.time / 1000000.0
+ if not options.adjustbaud:
+ byteadjust = 0.0
+
+ if options.serial:
+ # Read from serial port
+ try:
+ import serial
+ except ImportError:
+ print """
+Unable to find pyserial package ( http://pyserial.sourceforge.net/ ).
+On Linux machines try: yum install pyserial
+Or: apt-get install python-serial
+"""
+ sys.exit(1)
+ ser = serial.Serial(serialport, baud, timeout=0)
+ else:
+ # Read from a file
+ ser = open(serialport, 'rb')
+ import fcntl
+ import os
+ fcntl.fcntl(ser, fcntl.F_SETFL
+ , fcntl.fcntl(ser, fcntl.F_GETFL) | os.O_NONBLOCK)
+
+ if options.calibrate_read:
+ calibrateserialread(ser, byteadjust)
+ return
+ if options.calibrate_write:
+ calibrateserialwrite(ser, byteadjust)
+ return
+
+ logname = time.strftime("seriallog-%Y%m%d_%H%M%S.log")
+ f = open(logname, 'wb')
+ readserial(ser, f, byteadjust)
+
+if __name__ == '__main__':
+ main()
