tio(1) User Commands tio(1) NAME tio - a serial device I/O tool SYNOPSIS tio [<options>] <tty-device|profile|tid> DESCRIPTION tio is a 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 fol- lowing 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. -a, --auto-connect new|latest|direct Automatically connect to serial device according to one of the fol- lowing strategies: new Automatically connect to first new appearing serial de- vice. latest Automatically connect to latest registered serial device. direct Connect directly to specified TTY device. All the listed strategies automatically reconnects according to strategy if device is not available or connection is lost. Default value is "direct". --exclude-devices <pattern> Exclude devices by pattern ('*' and '?' supported). --exclude-drivers <pattern> Exclude drivers by pattern ('*' and '?' supported). --exclude-tids <pattern> Exclude topology IDs by pattern ('*' and '?' supported). -n, --no-reconnect Do not reconnect. This means that tio will exit if it fails to connect to device 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") epoch Seconds since Unix epoch (1970-01-01) Default format is 24hour --timestamp-timeout <ms> Set timestamp timeout value in milliseconds. This value only takes effect in hex output mode where timestamps are only printed after elapsed timeout time of no output activity from tty device. Default value is 200. -l, --list List available targets (serial devices, TIDs, configuration pro- files). -L, --log Enable log to file. The log file will be automatically named using the following format tio_TARGET_YYYY-MM-DDTHH:MM:SS.log. Target being the command line target such as tty-device, tid, or configuration profile. The filename can be manually set using the --log-file option. --log-file <filename> Set log filename. --log-directory <path> Set log directory path in which to save automatically named log files. --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 to the serial device or output from the serial device. The following mapping flags are sup- ported: ICRNL Map CR to NL on input (unless IGNCR is set) IGNCR Ignore CR on input IFFESCC Map FF to ESC-c on input INLCR Map NL to CR on input INLCRNL Map NL to CR-NL on input IMSB2LSB Map MSB bit order to LSB 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 ONULBRK Map nul (zero) to send break signal on output OIGNCR Ignore CR on output If defining more than one flag, the flags must be comma separated. --input-mode normal|hex|line Set input mode. In normal mode input characters are sent immediately as they are typed. In hex input mode bytes can be sent by typing the two-character hexadecimal representation of the 1 byte value, e.g.: to send 0xA you must type 0a or 0A. In line input mode input characters are sent when you press enter. The only editing feature supported in this mode is backspace. Default value is "normal". --output-mode normal|hex|hexN Set output mode. In hex mode each incoming byte is printed out as a 1 byte hex value. In hexN mode, N is a number less than or equal to 4096 which defines how many hex values will be printed before a line break. Default value is "normal". -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. --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". --mute Mute tio messages. --script <string> Run script from string. --script-file <filename> Run script from file with filename. --script-run once|always|never Run script on connect once, always, or never. Default value is "always". --exec <command> Execute shell command with I/O redirected to device -v, --version Display program version. -h, --help Display help. KEY COMMANDS 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 com- mand key. These sequences are intercepted as key 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 trans- mitted and data received but not read) ctrl-t g Toggle serial port line ctrl-t i Toggle input mode ctrl-t l Clear screen ctrl-t L Show line states (DTR, RTS, CTS, DSR, DCD, RI) ctrl-t m Change mapping of characters on input or output ctrl-t o Toggle output mode ctrl-t p Pulse serial port line ctrl-t q Quit ctrl-t r Run script ctrl-t R Execute shell command with I/O redirected to device ctrl-t s Show TX/RX statistics ctrl-t t Toggle line timestamp mode ctrl-t v Show version ctrl-t x Send file using the XMODEM-1K or XMODEM-CRC protocol (prompts for file name and protocol) ctrl-t y Send file using the YMODEM protocol (prompts for file name) ctrl-t ctrl-t Send ctrl-t character SCRIPT API Tio suppots Lua scripting to easily automate interaction with the tty de- vice. In addition to the standard Lua API tio makes the following functions available: expect(string, timeout) Expect string - waits for string to match or timeout before continu- ing. Supports regular expressions. Special characters must be es- caped with '\\'. Timeout is in milliseconds, defaults to 0 meaning it will wait forever. Returns 1 on successful match, 0 on timeout, or -1 on error. On successful match it also returns the match string as second return value. read(size, timeout) Read from serial device. If timeout is 0 or not provided it will wait forever until data is ready to read. Returns number of bytes read on success, 0 on timeout, or -1 on er- ror. On success, returns read string as second return value. Also emits a single timestamp to stdout and log file per options.timestamp and op- tions.log. read_line(timeout) Read line from serial device. If timeout is 0 or not provided it will wait forever until data is ready to read. Returns number of bytes read on success, 0 on timeout, or -1 on er- ror. On success, returns the string that was read as second return value. Also emits a single timestamp to stdout and log file per op- tions.timestamp and options.log. write(string) Write string to serial device. Returns number of bytes written on success or -1 on error. send(file, protocol) Send file using x/y-modem protocol. Protocol can be any of XMODEM_1K, XMODEM_CRC, YMODEM. tty_search() Search for serial devices. Returns a table of number indexed tables, one for each serial device found. Each of these tables contains the serial device information accessible via the following string indexed elements "path", "tid", "uptime", "driver", "description". Returns nil if no serial devices are found. set{line=state, ...} Set state of one or multiple tty modem lines. Line can be any of DTR, RTS, CTS, DSR, CD, RI State is high, low, or toggle. sleep(seconds) Sleep for seconds. msleep(ms) Sleep for milliseconds. exit(code) Exit with exit code. 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 configuration profiles which can be activated from the command-line when starting tio. tio will try to match the user input to a configuration profile 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 configu- ration 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-reconnect Do not reconnect log Enable log to file log-file Set log filename log-directory Set log directory path in which to save automati- cally named log files. log-append Append to log file 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 timestamp-timeout Set timestamp timeout map Map characters on input or output color Colorize tio text using ANSI color code ranging from 0 to 255 input-mode Set input mode output-mode Set output mode socket Set socket to redirect I/O to prefix-ctrl-key Set prefix ctrl key (a..z or 'none', default: t) rs-485 Enable RS-485 mode rs-485-config Set RS-485 configuration alert Set alert action on connect/disconnect mute Mute tio messages script Run script from string script-file Run script from file script-run Run script on connect exec Execute shell command with I/O redirected to de- vice It is possible to include the content of other configuration files using the include directive like so: "[include <file>]". CONFIGURATION FILE EXAMPLES To change the default configuration simply set options like so: [default] baudrate = 9600 databits = 8 parity = none stopbits = 1 color = 10 line-pulse-duration = DTR=200,RTS=400 Named configuration profiles can be added via labels: [rpi3] device = /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTGQVXBL-if00-port0 baudrate = 115200 color = 11 Activate the configuration profile by name: $ tio rpi3 Which is equivalent to: $ tio -b 115200 -c 11 /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FT- GQVXBL-if00-port0 A configuration profile can also be activated by its pattern which supports regular expressions: [usb-devices] pattern = ^usb([0-9]*) device = /dev/ttyUSB%m1 baudrate = 115200 Activate the configuration profile by pattern match: $ tio usb12 Which becomes equivalent to: $ tio -b 115200 /dev/ttyUSB12 It is also possible to combine use of configuration profile 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\n" expect -i $uart "prompt> " send -i $uart "ls -la\n" expect -i $uart "prompt> " It is also possible to use tio's own simpler expect/send script functional- ity to e.g. automate logins: $ tio --script 'expect("login: "); write("root\n"); expect("Pass- word: "); write("root\n")' /dev/ttyUSB0 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 (assum- ing 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_FT- GQVXBL-if00-port0 Pipe command to serial device and wait for line response within 1 second: $ echo "*IDN?" | tio /dev/ttyACM0 --script "expect('\r\n', 1000)" --mute Likewise, to pipe data from file to the serial device: $ cat data.bin | tio /dev/serial/by-id/usb-FTDI_TTL232R-3V3_FT- GQVXBL-if00-port0 Map NL to CR-NL on input from device and DEL to BS on output to device: $ tio --map INLCRNL,ODELBS /dev/ttyUSB0 Enable RS-485 mode: $ tio --rs-485 --rs-485-config=RTS_ON_SEND=1,RX_DURING_TX /dev/ttyUSB0 Manipulate DTR and RTS lines upon first connect to reset connected micro- controller: $ tio --script "set{DTR=high,RTS=low}; msleep(100); set{RTS=toggle}" --script-run once /dev/ttyUSB0 WEBSITE Visit https://tio.github.io AUTHOR Maintained by Martin Lund <martin.lund@keep-it-simple.com>. tio 3.9 2025-04-13 tio(1)
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | KEY COMMANDS | SCRIPT API | CONFIGURATION FILE | CONFIGURATION FILE EXAMPLES | EXAMPLES | WEBSITE | AUTHOR
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=tio&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>