Software Switching Scenarios
Assume a user wishes to switch back and forth between a V.25bis application
and Smartcom without changing cable connections, DIP switch settings (assume
"UP UP") or cycling power. When they obey the convention of reserving
stored profile 0 for normal AT command operation (S94=0), Smartcom can always
gain control of the modem by issuing ATZ with DTR low. Thus Smartcom functions
normally regardless of the previous state of the modem.
Assume the V.25bis application does not know about Hayes extensions to V.25bis,
and requires the modem to be already in V.25bis mode. As a configuration
step the user would set up stored profile 1 for the appropriate V.25bis
mode (async or sync). Then, before exiting Smartcom, they would issue an
ATZ1 command via a script. No DTR control is necessary since the modem is
already in AT command mode. Now the modem is ready for the V.25bis application.
Instead of using a script the user could put a Z1 command in the "Send after
hang-up" connection setting. Then Smartcom always switches the modem
to V.25bis mode on termination of the connection. If the user stayed in
Smartcom and started another connection, Smartcom would regain control of
the modem via the ATZ command described above.
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