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Chapter 14: DTE Interface Commands snd S-Register Settings
14.5.3 RTS C
ONTROL
Request To Send is the signaling circuit used to indicate to the attached ISDN
TA/V that the computer/terminal wants to send information. How this signal
is treated by the ISDN TA/V is determined by the
&R
command.
&R0
Normal RS-232 signaling. In general this requires the DTE to
switch RTS on whenever it wants to transmit data.
&R1
RTS is ignored.
&R2
RTS input controls the remote modem’s DCD signal using
simulated control carrier. To ensure correct operation of this
facility, the remote ISDN TA/V must be configured with its
DCD signaling command set to
simulated control carrier
. This
option should be selected where the DTE requires DCD to
toggle on and off in a simulated half duplex operation.
14.5.4 CTS C
ONTROL
Clear To Send is the signaling circuit used to indicate to the attached
computer/terminal that the ISDN TA/V is ready to receive information from
the DTE. How this signal is treated by the ISDN TA/V is determined by the
\D
command. Note that CTS ignores RTS when RTS flow control is enabled.
\D0
CTS is forced on at all times.
\D1
Normal RS-232 signaling. CTS is always on when the ISDN
TA/V is off-line, CTS follows RTS when on-line.
\D2
CTS is turned off for 1 or 2 seconds upon a disconnection.
\D3
The state of CTS follows the state of DTR.
14.5.5 RTS/CTS D
ELAY
The length of time the ISDN TA/V will wait after receiving RTS, before
raising CTS to the DTE, is configured into one of the ISDN TA/V’s
S-Register memory locations using the command
S26=
n
(where
n
represents
the delay in 10 millisecond increments). Definable in the range 0 to 255, the
factory setting being
0
milliseconds.
