NAME

ttytest - async read-write test and logical stub for terminal lines

SYNOPSIS

ttytest [options] <tty_dev>

DESCRIPTION

ttytest program is small and simply console test of serial lines (connection between two serial devices). The idea of test is in asynchronous writing test sequence into serial device and, at the same time, reading this test sequence from same device and output data to terminal (tty). For creating a data loopback can be used the standard serial port hardware stub or two serial ports, witch are connected with Nullmodem cable, in the late case at one side must be run ttytest in stub mode (see --mode option). If the result of testing is well then ttytest print "staircase" of unterminated test sequence e.i.:

test test test test test
test test test test test
test test test test test
test test test test test
test test test test test
test test test test test
test test test test test
test test test test test

OPTIONS

ttytest support short and long options of POSIX.

-h --help

Show command line help.

-V --version

Show version information.

-v --verbose

Increase verbosity (debug output).

-dSTRING, --data-string=STRING

Option customise the test STRING. Value:

"test test test test test"

is used by default.

EXAMPLE: ttytest --data-string="THIS IS A CUSTOM TEST STRING!!!"

-e, --enum-strings

If this option is set then the data-string is enumerated before write to device. Seqence is :

1 test test test test test
2 test test test test test
3 test test test test test
4 test test test test test

-u, --no-offset

this option disable autoinsert periodical offset ( "staircase") before test string

test test test test test
test test test test test
test test test test test
test test test test test

-pSECONDS, --pause=SECONDS

Option set a sleep interval in SECONDS ( decimal notation can be used ) before start of test ( no pause by default )

-mMODE, --mode=MODE

Option set a start MODE of ttytest. The MODE can be set into values "loopback", "read", "stub", "terminal" and "write". Value of MODE is case insensitive.

loopback: in this ( default ) mode the ttytest creates a two async threads for receiver and transmitter. The transmitter thread of ttytest write the test STRING configured by -d, -e, -u options into serial device (<tty_dev>) . Transmitter process can be controlled by -a, -w and -q options. At the same time, the receiver thread read data from same device and write received data to ttytests standard output.

stub: in this mode the ttytest implement a "logical stub". Program read any data from serial device ( <tty_dev> ) and write this data backward. The readed data writted to ttytests standard output as the same in loopback mode

terminal: is same as loopback, so transmitter read data from standard input ( keyboard ) and write it to serial device ( <tty_dev> ).

read: in this mode work only receiver.

write: in this mode work only transmitter.

-a, --adaptive-tx

if this option is set the transmitter support output queue with maximal empty state. For control of the queue transmitter use a statistic from TIOCGICOUNT IOCTL return. If -q or -w options are presented then -a has no effect.

-w, --wait-tx

if this option is set then the transmitter wait ( tcdrain function used ) of complete data transfer after writing every test STRING

-qCOUNT, --queue-size=COUNT

this option set the maximal COUNT of characters in the output transmitter queue. Transmitter use a TIOCOUTQ IOCTL for control of the queue size.

-s, --send-interval=SECONDS

the option set a time between sending of two test strings in SECONDS ( decimal notation can be used ) By default the sended data stream is unterminated.

-x, --hex-dump

if this option is set then the readed from serial device ( <tty_dev> ) bytes printed to output as hex dump. The option has effect only in sttub mode.

-BBAUD, --tty-baud=BAUD

set a tty BAUD rate ( 50, 100, 200 ... )

-WBITS, --tty-databits=BITS

set a data BITS count ( 1..8 )

-SBITS, --tty-stopb=BITS

set a tty stop BITS ( 1, 1.5, 2 )

-PPARITY, --tty-parity=PARITY

set PARITY check control. Value of PARITY can be one of "no", "odd","even", "mark" and space

-R, --tty-crtscts

RTS/CTS flow control can be used

-C, --tty-codepage

tty remote codepage in iconv style (MTK-2 included)

-N, --tty-nonprint_show

tty show nonprintable registry switches chars (in MTK encoding)

-U, --mtk-rprefix

tty registry chars in MTK encoding must be prefixed

-X, --tty-xonxoff

Xon/Xoff flow control can be used

-D, --tty-dsr

reciever is DSR sensibility

EXAMPLES

Quick usage:

Connect COM1 and COM2 ports with nullmodem cable
Open two consoles
Execute at one console the command
ttytest --mode=stub /dev/ttyS1
Execute at two console the command
ttytest --mode=loop /dev/ttyS0

Or

Connect a hardware stub to COM1 port
Open a console and execute the command
ttytest /dev/ttyS0

See at consoles the "staircase" of test strings.

SEE ALSO

stty(1) ioctl_list(2)