PacComm TINY-2 - Page 28

OPERATING INSTRUCTIONS Flow Control
use XON/XOFF flow control, which is enabled by setting Xflow
ON. The special flow control characters are set to < ~S >
and < -Q> by default. The commands XON and XOff
set the characters which will be sent to the terminal by the packet
controller, and the commands STArt and STOp set the charac-
ters to be sent to the packet controller by the terminal. Your
computer may receive as many as 4 characters from the packet
controller after sending a ST »p character, since some charac-
ters may already be “enroute” through serial I/O chips.
If you send a STOp (STArt) character to the packet controller
when it is already stopped (started), the character will be ig-
nored. If the STOp and STArt character are the same character,
this character will “toggle” the output, turning it off if it is on,
and on if it is off.
You can disable XON/XOFF flow control in one direction only
by setting the appropriate flow control characters to 0. If you do
this, the packet controller will automatically use CTS flow con-
trol to stop input from the terminal. KON/XOFF flow control is
normally
disabled
in
Transparent
Mode,
since
all
characters
are
treated as data. If you cannot use RTS/CTS flow control, you
may enable the XON and XOff characters (the commands from
the
packet
controller
to
the
terminal)
by
setting
TXFlow
ON
and
Xflow ON. The STArt and STOp characters (the commands to
the packet controller from the terminal) can be enabled in
Transparent Mode by setting TRFlow ON. Note that the mode
is no longer truly transparent when these features are enabled.
Hardware Flow Control
Hardware flow control is less likely to depend on the program.
ming of a particular communications program. RT'S and CTS
are normally used for flow control signals in Transparent Mode.
The
command
Xflow
OFF
enables
hardware
flow
control
in
Converse Mode and Command Mode. Your computer may
receive as many as 2 characters after it signals the packet con-
troller to stop sending, since some characters may already be
“enroute”
through
serial
I/O
chips.
Refer
to
the
TECHNICAL
REFERENCE MANUAL for details on the interface required
for hardware flow control.
Type-in Flow Control
Type-in
flow
control,
enabled
with
the
command
FLow,
is
really
a
display
feature
which
keeps
the
packet
controller
from
inter-
rupting
you
with
incoming
packets.
As
soon
as
you
type
the
first
character
of
a
line,
the
packet
controller
will
put
a“
old”
on
all
output
(except
for
echoing
your
input).
The
“hold”
remains
in
effect
until
you
type
a
<CR>
to
end
the
command
line,
or
a
Operating
Manual,
4th
Ed.
©
PacComm,
1990
21