Davex/doc/help/GSBuff

gsbuff -- examine or set sizes of IIgs serial port buffers

syntax:  gsbuff <portnum> [-i <integer>] [-o <integer>]

ex:      gsbuff 1           --shows printer buffer info
         gsbuff 2           --shows moddem buffer info
         gsbuff 1 -o 20000  --sets printer output buffer size
                              to 20000 bytes
         gsbuff 2 -i 65535  --sets modem input buffer size to
                              65535 bytes

'gsbuff' lets you change the size of the input and output
buffers on the Apple IIgs serial ports (normally, port 1
is used for a printer and port 2 is used for a modem).

You should turn on buffering in the control panel (under
Printer Port or Modem Port) before setting up buffers with
'gsbuff'.  (When you do this, the ROM allocates bufers that
are only 2048 bytes long.)

Use -i to set the input buffer size and -o to set the
output buffer size.  Buffer sizes must be in the range 1
to 65535 bytes.  Note that 'gsbuff' always allocates NEW
memory for buffering and never frees up previously-allocated
memory.

After allocating a buffer with 'gsbuff', it is recommended
that you use Apple-Ctrl-RESET or "boot -i" if you restart
your system (rather than "PR#n" from BASIC or "boot -sn"
from Davex).  This will insure that the ROM does not try
to use a buffer that is no longer present.

NOTE:  Printer buffering has very limited usefullness with
the current Apple IIgs ROM (version 01; see 'deschw'), since
the ROM empties your printer buffer whenever something new
is printed.  If you are willing to always wait until your
previous document is done printing before printing anything
else, then buffering will be useful to you.