Verilink Productivity 500 (34-00236) Product Manual - Manual (Page 65)

Synchronous Operation 500 TA Page 65
Chapter 9 Synchronous Operation
SYNCHRONOUS MODES
The 500 TA supports two synchronous modes. Operation in each of these
modes is described below.
Synchronous Mode 1 Sync Pause Mode
When a connection is made, the 500 TA delays for 5 seconds (configurable
with the S25 command) before monitoring DTR.
This delay serves two purposes. If separate dialing and communication termi-
nals are used, this allows the terminal operator to switch the cable between the
two. If separate dialing and communications software is being used on the
same terminal, the delay allows time for the dialing software to complete and
the communications software to initialize and turn DTR on.
After the 500 TA connects, the DSR, CD, and CTS pins will be high. This can
be used by the DTE as an indication to begin sending synchronous data to the
500 TA.
The 500 TA disconnects if it detects an on-to-off transition of the DTR pin
when &D0 is not in effect, or it receives a disconnect message from the switch.
After a disconnect, the 500 TA returns to the offline state. If the 500 TA is set
to auto answer, it will only answer when DTR is on or &D0 is in effect. If you
do not want the 500 TA to answer, DTR must remain low for at least 8 seconds
after the ringing ends.
Synchronous Mode 2 Dial Stored Number Mode
The 500 TA will automatically dial the telephone number stored in directory
entry number 0 when it detects an off-to-on transition of the DTR pin.
Once the 500 TA connects, the DSR, CD, and CTS pins will be high to indicate
to the DTE that it can begin sending synchronous data.
The 500 TA disconnects upon detecting an on-to-off transition of the DTR pin
when &D0 is not in effect, or receiving a disconnect message from the switch.
After disconnecting, the 500 TA hangs up and returns to the offline state.
If the 500 TA is set to auto answer, it will only answer when DTR is on or &D0
is in effect. If you do not want the 500 TA to answer, DTR must remain off for
at least 8 seconds after the ringing ends. After that time, if DTR turns on, the
500 TA will originate a call. If DTR turns on during the ringing process, but
before the required ring count is reached, the 500 TA will not originate a call.