tio(1)

NAME
tio - a simple serial device I/O tool

SYNOPSIS

tio [<options>] <tty-device|sub-config>

DESCRIPTION

tio is a simple serial device tool which features a straightforward command-line and configuration file interface to easily connect to serial TTY devices for basic I/O operations.

OPTIONS

-b, --baudrate <bps>
    Set baud rate [bps] (default: 115200).

-d, --databits 5|6|7|8
    Set data bits (default: 8).

-f, --flow hard|soft|none
    Set flow control (default: none).

-s, --stopbits 1|2
    Set stop bits (default: 1).

-p, --parity odd|even|none|mark|space
    Set parity (default: none). Note: With mark parity the parity bit is always 0. With space parity the parity bit is always 1. Not all platforms support mark and space parity.

-o, --output-delay <ms>
    Set output delay [ms] inserted between each sent character (default: 0).

-O, --output-line-delay <ms>
    Set output delay [ms] inserted between each sent line (default: 0).

--line-pulse-duration <duration>
    Set the pulse duration [ms] of each serial port line using the following key value pair format in the duration field: <key>=<value> Each key represents a serial line. The following keys are available:

    DTR
    Data Terminal Ready

    RTS Request To Send

    CTS Clear To Send

    DSR Data Set Ready

    DCD Data Carrier Detect

    RI  Ring Indicator

    If defining more than one key value pair, the pairs must be comma separated. The default pulse duration for each line is 100 ms.

-n, --no-autoconnect
    Disable automatic connect. By default tio automatically connects to the provided device if present. If the device is not present, it will wait for it to appear and then connect. If the connection is lost (eg. device disconnects), it will wait for the device to reappear and then reconnect. However, if the --no-autoconnect option is provided, tio will exit if the device is not present or an established connection is lost.

-e, --local-echo
    Enable local echo.

-t, --timestamp
    Enable line timestamp.

--timestamp-format <format>
    Set timestamp format to any of the following timestamp formats:

    24hour
    24-hour format ("hh:mm:ss.sss")

    24hour-start
        24-hour format relative to start time

    24hour-delta
        24-hour format relative to previous timestamp

    iso8601
        ISO8601 format ("YYYY-MM-DDThh:mm:ss.sss")

    Default format is 24hour

-L, --list-devices
    List available serial devices by ID.

-l, --log
    Enable log to file. The filename will be automatically generated using the following format tio_DEVICE_YYYY-MM-DDTHH:MM:SS.log. The filename can be manually set using the --log-file option.

--log-file <filename>
    Set log filename.

--log-append
    Append to log file.

--log-strip
    Strip control characters and escape sequences from log.

-m, --map <flags>
    Map (replace, translate) characters on input or output. The following mapping flags are supported:

    ICRNL
    Map CR to NL on input (unless IGNCR is set)

    IGNCR
        Ignore CR on input

    INLCR
        Map NL to CR on input

    INLCRNL
        Map NL to CR-NL on input

    OCRNL
        Map CR to NL on output

    ODELBS
        Map DEL to BS on output

    ONLCRNL
        Map NL to CR-NL on output

    OLTU
        Map lowercase characters to uppercase on output

    MSB2LSB
        Map MSB bit order to LSB on output

    If defining more than one flag, the flags must be comma separated.

-x, --hexadecimal
    Enable hexadecimal mode.

-c, --color 0..255|bold|none|list
    Colorize tio text using ANSI color code value ranging from 0 to 255 or use "none" for no color or use "bold" to apply bold formatting to existing system color. Use "list" to print a list of available ANSI color codes. Default value is "bold".

-S, --socket <socket>
    Redirect I/O to socket. Any input from clients connected to the socket is sent on the serial port as if entered at the terminal where tio is running (except that ctrl-t sequences are not recognized), and any input from the serial port is multiplexed to the terminal and all connected clients. Sockets remain open while the serial port is disconnected, and writes will block. Various socket types are supported using the following prefixes in the socket field:

    unix:<filename>
    Unix Domain Socket (file)

    inet:<port>
        Internet Socket (network)

    inet6:<port>
        Internet IPv6 Socket (network)

    If port is 0 or no port is provided default port 3333 is used.

    At present there is a hardcoded limit of 16 clients connected at one time.

-r, --response-wait
    Wait for line response then quit. A line is considered any string terminated with a NL character. If no line is received tio will quit after response timeout. Any tio text is automatically muted when piping a string to tio while in response mode to make it easy to parse the response.

--response-timeout <ms>
    Set timeout [ms] of line response (default: 100).

--rs-485
    Enable RS-485 mode.

--rs-485-config <config>
    Set the RS-485 configuration using the following key or key value pair format in the configuration field:

    RTS_ON_SEND=value
    Set logical level (0 or 1) for RTS pin when sending

    RTS_AFTER_SEND=value
        Set logical level (0 or 1) for RTS pin after sending

    RTS_DELAY_BEFORE_SEND=value
        Set RTS delay (ms) before sending

    RTS_DELAY_AFTER_SEND=value
        Set RTS delay (ms) after sending

    RX_DURING_TX
        Receive data even while sending data

    If defining more than one key or key value pair, they must be comma separated.

--alert none|bell|blink
    Set alert action on connect/disconnect. It will sound the bell once or blink once on successful connect. Likewise it will sound the bell twice or blink twice on disconnect. Default value is "none".

-v, --version
    Display program version.

-h, --help
    Display help.

KEYS

In session, all key strokes are forwarded to the serial device except the following key sequence: a prefix key (default: ctrl-t) followed by a command key. These sequences are intercepted as tio commands:

ctrl-t ?
    List available key commands

ctrl-t b
    Send serial break (triggers SysRq on Linux, etc.)

ctrl-t c
    Show configuration (baudrate, databits, etc.)

ctrl-t e
    Toggle local echo mode

ctrl-t f
    Toggle log to file

ctrl-t F
    Flush data I/O buffers (discard data written but not transmitted and data received but not read)

ctrl-t g
    Toggle serial port line

ctrl-t h
    Toggle hexadecimal mode

ctrl-t l
    Clear screen

ctrl-t L
    Show line states (DTR, RTS, CTS, DSR, DCD, RI)

ctrl-t p
    Pulse serial port line

ctrl-t q
    Quit

ctrl-t s
    Show TX/RX statistics

ctrl-t t
    Toggle line timestamp mode

ctrl-t U
    Toggle conversion to uppercase on output

ctrl-t v
    Show version

ctrl-t ctrl-t
    Send ctrl-t character

HEXADECIMAL MODE

In hexadecimal mode each incoming byte is printed out as a hexadecimal value.

Bytes can be sent in this mode by typing the two-character hexadecimal representation of the value, e.g.: to send 0xA you must type 0a or 0A.

CONFIGURATION FILE

Options can be set via configuration file using the INI format. tio uses the configuration file first found in the following locations in the order listed:

$XDG_CONFIG_HOME/tio/config

$HOME/.config/tio/config

$HOME/.tioconfig

Labels can be used to group settings into named sub-configurations which can be activated from the command-line when starting tio.

tio will try to match the user input to a sub-configuration by name or by pattern to get the TTY device and other options.

Options without any label change the default options.

Any options set via command-line will override options set in the configuration file.

The following configuration file options are available:

pattern
Pattern matching user input. This pattern can be an extended regular expression with a single group.

device
    TTY device to open. If it contains a "%s" it is substituted with the first group match.

baudrate
    Set baud rate

databits
    Set data bits

flow
    Set flow control

stopbits
    Set stop bits

parity
    Set parity

output-delay
    Set output character delay

output-line-delay
    Set output line delay

line-pulse-duration
    Set line pulse duration

no-autoconnect
    Disable automatic connect

log Enable log to file

log-file
    Set log filename

log-strip
    Enable strip of control and escape sequences from log

local-echo
    Enable local echo

timestamp
    Enable line timestamp

timestamp-format
    Set timestamp format

map Map characters on input or output

color
    Colorize tio text using ANSI color code ranging from 0 to 255

hexadecimal
    Enable hexadecimal mode

socket
    Set socket to redirect I/O to

prefix-ctrl-key
    Set prefix ctrl key (a..z, default: t)

response-wait
    Enable wait for line response

response-timeout
    Set line response timeout

rs-485
    Enable RS-485 mode

rs-485-config
    Set RS-485 configuration

alert
    Set alert action on connect/disconnect

CONFIGURATION FILE EXAMPLES

To change the default configuration simply set options like so:
    # Defaults
    baudrate = 9600
    databits = 8
    parity = none
    stopbits = 1
    color = 10
    line-pulse-duration = DTR=200,RTS=400

Named sub-configurations can be added via labels:
    [rpi3]
    device = /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTGQVXBL-if00-port0
    baudrate = 115200
    color = 11

Activate the sub-configuration by name:
    $ tio rpi3

Which is equivalent to:
    $ tio -b 115200 -c 11 /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTGQVXBL-if00-port0

A sub-configuration can also be activated by its pattern which supports regular expressions:
    [usb device]
    pattern = usb([0-9]*)
    device = /dev/ttyUSB%s
    baudrate = 115200

Activate the sub-configuration by pattern match:
    $ tio usb12

Which is equivalent to:
    $ tio -b 115200 /dev/ttyUSB12

It is also possible to combine use of sub-configuration and command-line options. For example:
    $ tio -l -t usb12

EXAMPLES

Typical use is without options:
    $ tio /dev/ttyUSB0

Which corresponds to the commonly used default options:
    $ tio -b 115200 -d 8 -f none -s 1 -p none /dev/ttyUSB0

It is recommended to connect serial TTY devices by ID:
    $ tio /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTGQVXBL-if00-port0

Using serial devices by ID ensures that tio automatically reconnects to the correct serial device if it is disconnected and then reconnected.

Redirect serial device I/O to Unix file socket for scripting:
    $ tio -S unix:/tmp/tio-socket0 /dev/ttyUSB0

Then, to issue a command via the file socket simply do:
    $ echo "ls -la" | nc -UN /tmp/tio-socket0 > /dev/null

Or use the expect command to script an interaction:
    #!/usr/bin/expect -f
    set timeout -1
    log_user 0
    spawn nc -UN /tmp/tio-socket0
    set uart $spawn_id
    send -i $uart "date
    expect -i $uart "prompt> "
    send -i $uart "ls -la
    expect -i $uart "prompt> "

Redirect device I/O to network file socket for remote TTY sharing:
    $ tio --socket inet:4444 /dev/ttyUSB0

Then, use netcat to connect to the shared TTY session over network (assuming tio is hosted on IP 10.0.0.42):
    $ nc -N 10.0.0.42 4444

Pipe command to the serial device:
    $ echo "ls -la" | tio /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTGQVXBL-if00-port0

Pipe command to the serial device and wait for line response (string ending with CR or NL):
    $ echo "*IDN?" | tio /dev/ttyACM0 --response-wait

In this mode, only the response will be printed.

Likewise, to pipe data from file to the serial device:
    $ cat data.bin | tio /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTGQVXBL-if00-port0

Enable RS-485 mode:
    $ tio --rs-485 --rs-485-config=RTS_ON_SEND=1,RX_DURING_TX /dev/ttyUSB0

WEBSITE

Visit https://tio.github.io

AUTHOR

Created by Martin Lund <martin.lund@keep-it-simple.com>.