Autzoo.1210
hacknews
utzoo!henry
Thu Dec 10 19:05:37 1981
6DZ problem solved
Figured out why trying to run a 6-DZ driver with 5-DZ hardware causes
crashes.  Stupid hardware.  The DZ is not smart enough to give a proper
interrupt when modem status changes (e.g. when somebody hangs up).  Hence
it is necessary for the driver to scan the DZs for status changes from
time to time.  This scan touches ALL the DZs that the driver is aware
of, regardless of which ones are/aren't in use.  The periodic scan is
started the first time somebody opens a DZ port.  All is explained.