1JPNEVULATOR(1) User Commands JPNEVULATOR(1)
2
6 jpnevulator - Just another serial sniffer
7
9 jpnevulator [OPTION]... <FILE>
10
12 jpnevulator is a handy serial sniffer. You can use it to send data on a
13 serial device too. You can read or write from/to one or more serial
14 devices at the same time.
15 In write (--write) mode data to be sent on the serial device(s) is read
17 from a file or stdin in base (--base) defined notation. Data is sent on
18 the serial device(s) line by line.
19 In read (--read) mode data to be read from the serial device(s) is
21 written to a file or stdout in base (--base) defined notation. Skim
22 through the options for several enhancements in the output. It's even
23 possible to pass(--pass) on the data between the several serial
24 devices.
25 Mandatory arguments to long options are mandatory for short options
27 too.
28 Generic options:
30 -B, --base=BASE
32 Specify the base unit of read/write bytes. Currently only
33 2=binary and 16=hexadecimal are supported. The default base unit
34 is hexadecimal.
35 Selecting hexadecimal as the base unit, the input format is FD
37 or 0xFD. Of course all input is treated case-insensitive. Spaces
38 may or may not be included in the input. So DEADBEEF is exactly
39 the same as DE AD BE EF.
40 Selecting binary as the base unit, the input format is 01000010.
42 Spaces may or may not be included in the input. So 01000010111
43 is exactely the same as 01000010 111. Yes, that's right! It's
44 perfectly fine to write less than 8 bits, excluding the leading
45 zeros. Please understand if doing so, spaces are needed to sepa‐
46 rate the individual bytes in this case, but that's obvious. If
47 no spaces are used, the parses reads the first 8 bits before it
48 continues with the next, as shown in the example above.
49 -l, --alias-separator
51 Use the given string as the alias separator. See --tty for more
52 information.
53 -f, --file=NAME
55 In write mode read the contents of the file given and send them
56 on the serial device(s) and in read mode write the contents of
57 the serial device(s) to the file given.
58 -h, --help
60 Shows a brief list of options.
61 -o, --count=BYTES
63 Exit after reading / writing the given amount of bytes.
64 -r, --read
66 Put the program in read mode. This way you read the data from
67 the given serial device(s) and write it to the file given or
68 stdout if none given. See the read options section for more
69 read specific options.
70 -t, --tty=NAME:ALIAS
72 The serial device to read from or write to. Use multiple times
73 to read/write from/to more than one serial device(s). For handy
74 reference you can also separate an alias from the tty name with
75 a collon ':'. If a collon is for some strange reason part of
76 your device name, you can use the --alias-separator option to
77 specify another separation string. If an alias is given it will
78 be used as the name of the serial device.
79 -v, --version
81 Output the version information, a small GPL notice and exit.
82 -w, --write
84 Put the program in write mode. This way you read data from a
85 given file or stdin if none given and write it to the serial
86 device(s) given. See the write options section for more write
87 specific options.
88 Read options:
90 -a, --ascii
92 Besides the normal output of the data, also display an extra
93 column with the data in the ASCII representation. Non printable
94 characters are displayed as a dot '.'. The ASCII data is dis‐
95 played after the normal data.
96 -b, --byte-count
98 Besides the normal output also display an extra column with the
99 current index number of the byte in the output. These numbers
100 are displayed in front of the normal output. When readin from
101 multiple serial devices at the same time the index number will
102 increase per serial device.
103 -C, --control
105 Monitor modem control bits (line enable, data terminal ready,
106 request to send, secondary TXD, secondary RXD, clear to send,
107 carrier detect, ring and data set ready) too and notify changes.
108 Use the --control-poll option to specify how often to poll for
109 the bits.
110 -D, --control-poll=MICROSECONDS
112 The control poll is the amount of microseconds to wait in
113 between two checks of the modem control bits if nothing else is
114 happening.
115 -P, --pass
117 This one passes all the data between the serial devices. Handy
118 if you want to put your serial sniffer in between the serial
119 devices you want to sniff.
120 -q, --pty=:ALIAS
122 The pseudo-terminal device to read from. Use multiple times to
123 read from more than one pseudo-terminal device(s). For handy
124 reference you can also use an alias to name the pty. Make sure
125 it starts with a collon ':'. Use the --alias-separator option if
126 you for some reason don't like to use a collon. If an alias is
127 given it will be used as the name of the pseudo-terminal device.
128 -e, --timing-delta=MICROSECONDS
130 The timing delta is the amount of microseconds between two bytes
131 that the latter is considered to be part of a new package. The
132 default is 100 miliseconds. Use this option in conjunction with
133 the --timing-print option.
134 -g, --timing-print
136 Print a line of timing information before every continues stream
137 of bytes. When multiple serial devices are given also print the
138 name or alias of the device where the data is coming from.
139 -i, --width=WIDTH
141 The number of bytes to display on one line. The default is 16.
142 -A, --append
144 Append to the output file instead of overwriting. The default is
145 to overwrite.
146 -S, --append-separator
148 Use the given string as the append separator. The string is pro‐
149 cessed and the '\n' sequence transforms into a real newline. So
150 far no other sequences do anything special. The default is a
151 single newline character.
152 Write options:
154 -c, --checksum
156 Append a single checksum byte to the line of data written to the
157 serial device(s) chosen. This checksum is a simple modulo 256
158 addition of all input bytes on a line.
159 -z, --crc8=POLY
161 Append a crc8 checksum to the line of data written to the serial
162 device(s) chosen. Use the optionally given poly as the polyno‐
163 mial. Specify the polynomial as hexadecimal value, as in 0x07
164 (the default).
165 -y, --crc16=POLY
167 Append a crc16 checksum to the line of data written to the
168 serial device(s) chosen. Use the optionally given poly as the
169 polynomial. Specify the polynomial as hexadecimal value, as in
170 0xA001 (the default).
171 -k, --delay-byte=MICROSECONDS
173 This delay is an optional amount of microseconds to wait in
174 between every input byte is sent on the serial device(s).
175 -d, --delay-line=MICROSECONDS
177 This delay is an optional amount of microseconds to wait in
178 between every input line is sent on the serial device(s).
179 -j, --fuck-up
181 This is the special fuck up option. When the calculation of a
182 checksum is chosen (see checksum and crc* options) the checkum
183 will be crippled on purpose. Carefully named after the special
184 Jan Arie de Bruin 'fuck up crc' button.
185 -n, --no-send
187 Do not actually send the bytes on the serial device(s). Rather
188 pointless, but seemed one day long ago to be a rather handy fea‐
189 ture.
190 -p, --print
192 Besided sending the data on the serial device(s) also write the
193 data to stdout.
194 -s, --size=SIZE
196 The maximum number of bytes per line to send on the serial
197 device(s). The default is 22, coming from back in the Cham2 days
198 of the program.
199
201 Normally, exit status is 0 if the program did run with no problem what‐
202 soever. If the exit status is not equal to 0 an error message is
203 printed on stderr which should help you solve the problem.
204
206 Order of bytes broke when reading several tty devices at once
207 The display of incoming bytes can be broke if you use multiple tty
209 devices to read from. At the moment I do not have a solution for this
210 problem. Since I use select() to watch the several tty devices and
211 after the select() I have to read() them one by one, I can not com‐
212 pletely 100% display which bytes came after which on different tty
213 devices. Take the example below:
214 $ jpnevulator --ascii --timing-print --tty /dev/ttyS0 --tty /dev/ttyUSB0 --read
216 2006-05-30 13:23:49.461075: /dev/ttyS0
217 00 00 05 3B 0D 00 00 05 ...;....
218 2006-05-30 13:23:49.461113: /dev/ttyUSB0
219 00 05 3B 0D 00 00 05 3B 0D ..;....;.
220 2006-05-30 13:23:49.473074: /dev/ttyS0
221 3B 0D 00 00 05 3B 0D ;....;.
222 2006-05-30 13:23:49.473105: /dev/ttyUSB0
223 00 12 05 06 39 00 12 05 06 39 1F 00 22 80 00 0E ....9....9.."...
224 $
225 And now see the order in which things really got sent on the line:
227 /dev/ttyS0:
229 00 00 05 3B 0D
230 /dev/ttyUSB0:
231 00 00 05 3B 0D
232 /dev/ttyS0:
233 00 00 05 3B 0D
234 /dev/ttyUSB0:
235 00 00 05 3B 0D
236 /dev/ttyS0:
237 00 00 05 3B 0D
238 /dev/ttyUSB0:
239 00 00 05 3B 0D 00 12 05 06 39 00 12 05 06 39 ...
240 As you can see /dev/ttyUSB0 receives the echo of all things sent by
242 /dev/ttyS0. This is exactly what happens. But since there does exist a
243 small time between the select() who is happy expressing something is
244 available and the read() who does get the available data, some extra
245 data will be available. I have no idea on how I can use high level sys‐
246 tem call like select() and read() and be still able to put the bytes in
247 the correct order. Anyone an idea?
248
250 Written by Freddy Spierenburg.
251
253 Report bugs to <freddy@snarl.nl>.
254
256 Copyright © 2006-2020 Freddy Spierenburg
257jpnevulator 2.3.5 May 2020 JPNEVULATOR(1)