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picocom(8)                                                          picocom(8)

       picocom - minimal dumb-terminal emulation program

       picocom [ options ] device

       As its name suggests, picocom is a minimal dumb-terminal emulation pro-
       gram. It is, in principle, very much like minicom(1) , only it's "pico"
       instead  of "mini"! It was designed to serve as a simple, manual, modem
       configuration, testing, and debugging tool. It has also  served  (quite
       well) as a low-tech "terminal-window" to allow operator intervention in
       PPP connection scripts (something like the  ms-windows  "open  terminal
       window  before / after dialing" feature). It could also prove useful in
       many other similar tasks.

       When picocom starts it opens the terminal (serial device) given as  its
       non-option argument. Unless the --noinit option is given, it configures
       the device to the settings specified by  the  option-arguments  (or  to
       some  default  settings),  and  sets  it  to "raw" mode. If --noinit is
       given, the initialization and configuration is skipped; the  device  is
       just  opened. Following this, picocom sets the standard-input and stan-
       dard-output to raw mode. Having done so, it goes in  a  loop  where  it
       listens  for  input from stdin, or from the serial port. Input from the
       serial port is copied to the standard output while input from the stan-
       dard  input is copied to the serial port.  picocom also scans its input
       stream for a user-specified control character, called the "escape char-
       acter"  (being by default "C-a"). If the escape character is seen, then
       instead of sending it to the serial-device, the program enters "command
       mode"  and  waits for the next character (which is called the "function
       character"). Depending on the value of the function character,  picocom
       performs  one  of  the  operations  described in the "Commands" section

       Commands are given to picocom by first keying  the  "espace  character"
       which  by  default  is "C-a" (see "Options" below on how to change it),
       and then keying one for the function (command) characters shown here.

       [escape character]
          Send the escape character to the serial port and return  to  "trans-
          parent"  mode.  This  means  that if the escape character ("C-a", by
          default) is typed twice, the program sends the escape  character  to
          the  serial  port,  and  remains  in transparent mode. This is a new
          behavior implemented in v1.4. Previously picocom used to ignore  the
          escape-character when it was entered as a function character.

          Exit  the  program: if the "--noreset" option was not given then the
          serial port is reset to its original settings before exiting; if  it
          was given the serial port is not reset.

          Quit  the  program *without* reseting the serial port, regardless of
          the "--noreset" option.

          Pulse the DTR line. Lower it for 1 sec, and then raise it again.

          Toggle the DTR line. If DTR is up, then lower it.  If  it  is  down,
          then raise it.

          Generate  a  break  sequence on the serial line. A break sequence is
          usually generated by marking (driving to logical one) the serial  Tx
          line  for  an amount of time coresponding to several character dura-

          Baud up. Increase the baud-rate. The  list  of  baud-rates  stepped-
          through by this command is: 300, 600, 1200, 2400, 4800, 9600, 19200,
          38400, 57600, 115200.

          Baud down. Decrease the baud-rate. The list of  baud-rates  stepped-
          through by this command is the same as for the "baud-up" command.

          Cycle through flow-control settings (RTS/CTS, XON/XOFF, none).

          Cycle through parity settings (even, odd, none).

          Cycle through databits-number settings (5, 6, 7, 8).

          Show  program  options  (like  baud  rate, data bits, etc). Only the
          options that can be modified online (through  commands)  are  shown,
          not those that can only be set at the command-line.

          Send (upload) a file (see "Sending and Receiving Files" below)

          Receive (download) a file (see "Sending and Receiving Files" below)

       After  performing  one  of  the above operations the program leaves the
       command mode and enters transparent  mode.  Example:  To  increase  the
       baud-rate by two steps, you have to type:

       C-a, C-u, C-a, C-u

       assuming of-course that "C-a" is the escape character.

       picocom  can send and receive files over the serial port using external
       programs that implement the respective protocols. In Linux typical pro-
       grams for this purpose are:

       -- rx(1) - receive using the X-MODEM protocol

       -- rb(1) - receive using the Y-MODEM protocol

       -- rz(1) - receive using the Z-MODEM protocol

       -- sx(1) - send using the X-MODEM protocol

       -- sb(1) - send using the Y-MODEM protocol

       -- sz(1) - send using the Z-MODEM protocol

       -- ascii-xfr(1) - receive or transmit ASCII files

       The  name  of,  and the command-line options to, the program to be used
       for transmitting files are given by the "--send-cmd" option.  Similarly
       the  program  to  receive  files,  and  its  argumets, are given by the
       "--receive-cmd" option. For example, in order to start a  picocom  ses-
       sion that uses "sz" to transmit files, and "rz" to receive, you have to
       say something like this:

       picocom --send-cmd "sz -vv" --receive-cmd "rz -vv"

       During the picocom session, if you key the "send" or "receive" commands
       (e.g.  by  pressing  C-a,  C-s, or C-a, C-r) you will be prompted for a
       filename. At this prompt you can enter one or more file-names, and  any
       additional  arguments  to  the transmission or reception program. After
       that, picocom will start the the external program as specified  by  the
       "--send-cmd",  or  "--receive-cmd"  option,  and with any filenames and
       additional arguments you may have supplied. The standard input and out-
       put  of  the external program will be connected to the serial port. The
       standard error of the external program will be connected to the  termi-
       nal  which---while  the  program  is running---will revert to canonical
       mode. Pressing 'C-c' while the external program is running will  prema-
       turely terminate it, and return control to picocom

       picocom accepts the following command-line options

       --baud | -b
          Defines the baud-rate to set the serial-port (terminal) to.

       --flow | -f
          Defines the flow-control mode to set the serial-port to. Must be one

          -- 'x' for xon/xoff (software) mode

          -- 'h' for hardware flow control (RTS/CTS)

          -- 'n' for no flow control

          (Default: 'n')

       --parity | -p
          Defines the parity mode to set the serial-port to. Must be one of:

          -- 'o' for odd parity mode.

          -- 'e' for even parity mode.

          -- 'n' for no parity, mode.

          (Default: 'n')

       --databits | -d
          Defines the number of data bits in every character. Must be one  of:
          5, 6, 7, 8

          (Default: 8)

       --esacpe | -e
          Defines the character that will make picocom enter command-mode (see
          description above). If 'x' is given,  then  C-x  will  make  picocom
          enter command mode.

          (Default: 'a')

       --noinit | -i
          If  given,  picocom  will not initialize, reset, or otherwise meddle
          with the serial port at start-up. It will just open it. This is use-
          ful,  for  example,  for  connecting  picocom  to  already-connected
          modems, or already configured ports without terminating the  connec-
          tion,  or  altering the settings. If required serial port parameters
          can then be adjusted at run-time by commands.

       --noreset | -r
          If given, picocom will not *reset* the serial port when exiting.  It
          will just close the filedes and do nothing more. This is useful, for
          example, for leaving modems connected when exiting  picocom  picocom
          using the "Quit" command (instead of "Exit"), which never resets the
          serial port. If "--noreset" is given then "Quit" and  "Exit"  behave
          essentially the same.

       --nolock | -l
          If  given, picocom will *not* attempt to lock the serial port before
          opening it. Normally picocom attempts to get a UUCP-style  lock-file
          (e.g. "/var/lock/LCK..ttyS0") before opening the port. Failing to do
          so, results in the program exiting after emitting an  error-message.
          It  is  possible  that  your picocom binary is compiled without this

       --send-cmd | -s
          Specifies the external program (and any arguments to it)  that  will
          be used for transmitting files.

          Default: "sz -vv"

       --receive-cmd | -v
          Specifies  the  external program (and any arguments to it) that will
          be used for receiving files.

          (Default: "rz -vv")

       --help | -h
          Print a short help message describing the command-line options.

       picocom was written by Nick Patavalis (npatATefault.net)

       The   latest   version   of   "picocom"   can   be   downloaded   from: