Problem converting TPro BBS from AppleCat to SSC+modem

[gledford@fcircus.sat.tx.us (Gordon Ledford)]

    Once upon a time, some friends of mine had a TPro BBS on a IIe.
    Lightning struck, and parts of the system were destroyed, including the
    AppleCat card that the BBS was using.  Now, years later, we are trying
    to resurrect the system by using a Super Serial Card (SSC) and a modem
    in the place of the AppleCat.  Although the version of TPro that the
    system is based on is very old, it seemed like a fairly straightforward
    procedure to reconfigure the system for the new setup.  Having tried
    this, we have reached a point where it looks like we are almost there,
    save for one problem:  TPro only seems to be `listening' to the SSC
    when it is trying to establish a connection (the user logging on has to
    press a return); thereafter, all transmissions from the user are
    ignored, so he can't enter his name, password, or anything else.

    The SSC seems to work fine.  I can pr#2 and in#2 and do stuff from a
    remote terminal all day.  And when TPro is trying to figure out the
    baud rate of the connection it will take the return character from the
    remote just fine.  But after that...  nothing.

    It appears that we have TPro version 4.2.  However, with the passing of
    the years the situation has become pretty disorganized, and some things
    are kind of unclear.  I have tried to bring up an (almost) unmodified
    version of TPro with the same basic results (modifications made were so
    that it would attempt a startup and logon from floppies).  What I am
    hoping is that there is some configuration detail I am missing (which
    is possible, since I haven't found the TPro documentation yet).  I am
    fairly confident that the SSC configuration is good, unless TPro
    requires something unusual.

    If someone out there can share some insight into this situation we
    would really appreciate it.

    Thanks.

    Gordon Ledford                              gledford@fcircus.sat.tx.us