Subject: Re: Serial Port Funkiness
To: NetBSD/Mac68k Mailing List <port-mac68k@NetBSD.ORG>
From: Dameon D. Welch <dwelch@uplink.com>
List: port-mac68k
Date: 10/28/1995 16:28:40
Quotes from the great literary masterpieces of Bill Studenmund:

> What exactly is the error? The new code will report two kinds of overflows,
> fifo and ring. If you're getting fifo overflows, the interrupt handler is
> not getting called often enough (or it's seeing overflows when they
> don't exist, not likely). 
> [...]
> If the error is a ring overflow, the second-half of the interrupt handler is
> not getting called often enough. The ring is the place where requests
> from the interrupt handler wait for the kernel to process. I've not
> heard of problems here, but they'd be easy to fix. The ring is just an
> array which can be grown.

I have both errors -- they seem to alternate.

> I think most of the problem is that the fifo is the on-chip fifo, which only
> has 3 characters worth of space. :-(

Well that kind of sucks.

> Oh, what baud rate are you using? Are you doing lots of disk accesses?

28.8k FTP download, so yes, some disk access. It really seemed to be
apparent (the errors) when I was using X.

I'll be glad when I get my new PC, which I finally bit the bullet and
ordered today. Looking forward to running NetBSD or FreeBSD on a PC
instead of this slow old mac I've got, which will have to be sold to
pay for the new computer.

-- 
< Dameon D. Welch (dwelch@uplink.com, http://www.uplink.com/uplink/ ) >
     "That's not a lie, it's a terminological inexactitude."
          -- Alexander Haig