STTY (II)                    6/12/72                    STTY (II)





NAME            stty  --  set mode of typewriter



SYNOPSIS        (file descriptor in r0)

                sys stty; arg  / stty = 31.

                ...

          arg:  dcrsr; dctsr; mode



DESCRIPTION     stty sets mode bits for a typewriter whose file

                descriptor is passed in r0.  First, the system

                delays until the typewriter is quiescent.  Then,

                the argument dcrsr is placed into the typewri-

                ter's receiver control and status register, and

                dctsr is placed in the transmitter control and

                status register.  The DC-11 manual must be con-

                sulted for the format of these words.  For the

                purpose of this call, the most important rĂ´le of

                these arguments is to adjust to the speed of the

                typewriter.



                The mode argument contains several bits which de-

                termine the system's treatment of the typewriter:



                   200  even parity allowed on input (e. g. for M37s)

                   100  odd parity allowed on input

                   040  raw mode: wake up on all characters

                   020  map CR into LF; echo LF or CR as LF-CR

                   010  echo (full duplex)

                   004  map upper case to lower on input (e. g. M33)

                   002  echo and print tabs as spaces

                   001  inhibit all function delays (e. g. CRTs)



                Characters with the wrong parity, as determined

                by bits 200 and 100, are ignored.



                In raw mode, every character is passed back imme-

                diately to the program.  No erase or kill pro-

                cessing is done; the end-of-file character (EOT),

                the interrupt character (DELETE) and the quit

                character (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 Ter-

                miNet 300's and other terminals without the new-

                line function).



                Additional bits in the high order byte of the

                mode argument are used to indicate that the ter-

                minal is an IBM 2741 and to specify 2741 modes.

                These mode bits are:



                   400  terminal is an IBM 2741

                  1000  the 2741 has the transmit interrupt feature

                        (currently ignored)

                  2000  use correspondence code conversion on output

                  4000  use correspondence code conversion on input

                        (currently ignored)



                Normal input and output code conversion for 2741s

                is EBCDIC (e. g. 963 ball and corresponding key-

                board).  The presence of the transmit interrupt

                feature permits the system to do read-ahead while

                no output is in progress.  In 2741 mode, the low

                order bits 331 are ignored.



SEE ALSO        stty(I), gtty(II)



DIAGNOSTICS     The error bit (c-bit) is set if the file descrip-

                tor does not refer to a typewriter.



BUGS            This call should be used with care.