Serial driver changes from v5 to v7

Hi folks,

Can anybody point me to what changed in serial comms
from FreeBSD 5.x to 6 and 7?

I'm using an admittedly ancient serial printer which
works perfectly on 5.x and fails under 6 and 7, with
the message "lp is not responding" under lprps.

It was hoped that the uart driver in 7-CURRENT might make
a difference, but no luck, same error. It's possible to
communicate interactively using cu, so there's nothing
wrong with the hardware. The printcap file has been
copied faithfully between OS versions, here it is:

lp|ps:\
:br#9600:lp=/dev/cuau0:mx#0:sf:sh:rw:sb:\
:fc#0177777:fs#003:ms=ixon,ixoff,-isig,igncr,cstopb,-echok:\
:af=/var/log/psacct:lf=/var/log/pslog:sd=/var/spool/output/pslpd:\
:if=/usr/local/libexec/psif:

The 5.x printcap used /dev/ttyd0, which does not exist in
the newer FBSD versions. Is cuau0 the wrong substitute?

If anybody's got a hint understandable by a non-programmer
I'd be most grateful for the enlightenment.

Thanks for reading,

bob prohaska

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