DCP Configuration
4-37
3920-A2-GN31-30
November 1996
Table 4-7
(5 of 8)
DTE Interface Configuration Options — Singleport Mode
A
CTS Control: Stndrd_RS232
Nxt Stndrd_RS232 Forced_On WinkWhenDisc Follows_DTR Follows_RTS
Clear-to-Send Control. CTS is a signal from the modem to the DTE indicating that it can accept data from the DTE.
Standard RS232 – In Synchronous mode, forces the state of CTS to follow the state of RTS in normal EIA-232-D
operation. The minimum time that elapses between CTS and RTS is determined by the RTS/CTS Delay configuration
option. Use this setting for most synchronous applications. In AT Command mode, CTS goes low just prior to DSR
going active and goes high when the modem enters Data mode. This operation prevents losing data in applications
which begin transmitting as soon as DSR and CTS are both active.
Forced On – CTS is forced ON at all times. Use this selection for most asynchronous applications.
Wink When Disconnect – CTS is normally forced ON, but is turned OFF for 1 to 2 seconds upon a disconnect. Use
this for most UNIX
r
applications.
Follows DTR – The state of CTS follows the state of DTR. When DTR turns ON, CTS turns ON. When DTR turns OFF,
CTS turns OFF.
Follows RTS – The state of CTS follows the state of RTS. When RTS turns ON, CTS turns ON. When RTS turns OFF,
CTS turns OFF.
NOTE: When CTS flow control or CTS/RTS flow control is enabled, CTS will turn ON and OFF regardless of the setting
of CTS Control.
The AT command for Forced On is \D0.
The AT command for Standard RS232 is \D1.
The AT command for Wink When Disconnect is \D2.
The AT command for Follows DTR is \D3.
The AT command for Follows RTS is \D4.
RTS/CTS Delay: 0msec
Nxt 0msec 10msec 50msec 150msec 600msec
Request-to-Send/Clear-to-Send Delay. RTS/CTS Delay sets the delay time between the modem receiving RTS from the
DTE and the modem sending CTS to the DTE.
NOTE: This delay is only valid in Async Direct mode and synchronous applications when it is necessary to have a short
delay between the time the DTE raises RTS and the time the modem presents CTS to allow the DTE to send
data.
NOTE: For this configuration option to be valid, both the RTS Action and the CTS Control configuration options must be
set to Stndrd RS232. If RTS Action is set to Ignore, RTS is always ON and this configuration option has no
effect.
The AT command is S-Register S26=
n, where n is a value from 0 to 255 in 10 millisecond increments.
