STTY(II) 12/15/74 STTY(II)
NAME
stty - set mode of typewriter
SYNOPSIS
(stty = 31.)
(file descriptor in r0)
sys stty; arg
...
arg: .byte ispeed, ospeed; .byte erase, kill; mode
stty(fildes, arg)
struct {
char ispeed, ospeed;
char erase, kill;
int mode;
} *arg;
DESCRIPTION
Stty sets mode bits and character speeds for the typewriter
whose file descriptor is passed in r0 (resp. is the first
argument to the call). First, the system delays until the
typewriter is quiescent. The input and output speeds are
set from the first two bytes of the argument structure as
indicated by the following table, which corresponds to the
speeds supported by the DH-11 interface. If DC-11, DL-11 or
KL-11 interfaces are used, impossible speed changes are ig-
nored.
0 (hang up dataphone)
1 50 baud
2 75 baud
3 110 baud
4 134.5 baud
5 150 baud
6 200 baud
7 300 baud
8 600 baud
9 1200 baud
10 1800 baud
11 2400 baud
12 4800 baud
13 9600 baud
14 External A
15 External B
In the current configuration, only 110, 150 and 300 baud are
really supported on dial-up lines, in that the code conver-
sion and line control required for IBM 2741's (134.5 baud)
must be implemented by the user's program, and the half-du-
plex line discipline required for the 202 dataset (1200
baud) is not supplied.
The next two characters of the argument structure specify
the erase and kill characters respectively. (Defaults are #
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STTY(II) 12/15/74 STTY(II)
and @.)
The mode contains several bits which determine the system's
treatment of the typewriter:
100000 Select one of two algorithms for backspace de-
lays
040000 Select one of two algorithms for form-feed and
vertical-tab delays
030000 Select one of four algorithms for carriage-re-
turn delays
006000 Select one of four algorithms for tab delays
001400 Select one of four algorithms for new-line de-
lays
000200 even parity allowed on input (e. g. for M37s)
000100 odd parity allowed on input
000040 raw mode: wake up on all characters
000020 map CR into LF; echo LF or CR as CR-LF
000010 echo (full duplex)
000004 map upper case to lower on input (e. g. M33)
000002 echo and print tabs as spaces
000001 hang up (remove `data terminal ready,' lead CD)
after last close
The delay bits specify how long transmission stops to allow
for mechanical or other movement when certain characters are
sent to the terminal. In all cases a value of 0 indicates
no delay.
Backspace delays are currently ignored but will be used for
Terminet 300's.
If a form-feed/vertical tab delay is specified, it lasts for
about 2 seconds.
Carriage-return delay type 1 lasts about .08 seconds and is
suitable for the Terminet 300. Delay type 2 lasts about .16
seconds and is suitable for the VT05 and the TI 700. Delay
type 3 is unimplemented and is 0.
New-line delay type 1 is dependent on the current column and
is tuned for Teletype model 37's. Type 2 is useful for the
VT05 and is about .10 seconds. Type 3 is unimplemented and
is 0.
Tab delay type 1 is dependent on the amount of movement and
is tuned to the Teletype model 37. Other types are unimple-
mented and are 0.
Characters with the wrong parity, as determined by bits 200
and 100, are ignored.
In raw mode, every character is passed immediately to the
program without waiting until a full line has been typed.
No erase or kill processing is done; the end-of-file charac-
ter (EOT), the interrupt character (DEL) and the quit char-
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STTY(II) 12/15/74 STTY(II)
acter (FS) are not treated specially.
Mode 020 causes input carriage returns to be turned into
new-lines; input of either CR or LF causes LF-CR both to be
echoed (used for GE TermiNet 300's and other terminals with-
out the newline function).
The hangup mode 01 causes the line to be disconnected when
the last process with the line open closes it or terminates.
It is useful when a port is to be used for some special pur-
pose; for example, if it is associated with an ACU used to
place outgoing calls.
This system call is also used with certain special files
other than typewriters, but since none of them are part of
the standard system the specifications will not be given.
SEE ALSO
stty(I), gtty(II)
DIAGNOSTICS
The error bit (c-bit) is set if the file descriptor does not
refer to a typewriter. From C, a negative value indicates
an error.
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