aragorn@archet.UUCP (Strider) (02/19/89)
I am trying to solve a problem which occurs on the IBM RT when it runs ACIS (BSD 4.3). The problem is as follows: the normal serial ports are either on an async/printer card or on what is called a 4 port adapter. The async card has no buffering and the 4 port card has 16 bytes of buffering. The problem is as follows: when one is trying to use a serial line at more than about 2400 BPS or sometimes even at slower speeds if other processes are running, the RT begins to have real problems. Basically, the interupts from the port don't get serviced often enough, the buffer overflows and ... anyway, this leads to UUCP problems, and the occasional crash. The question I have is whether there is a way of fixing this short of rewriting the device driver properly or getting a different card with substantially more buffering. I have heard that early versions of BSD running on the Vax had similar problems and that they were solved without writing a totally new driver or changing devices. I'm looking for helpful suggestions. Thanks. Bill Moran uunet!bywater!acheron!archet!aragorn or moran-william@cs.yale.edu