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From: Ralf.Brown@B.GP.CS.CMU.EDU
Newsgroups: comp.os.minix
Subject: Re: Bugs found installing V1.3
Message-ID: <22e34384@ralf>
Date: 19 Jul 88 12:41:40 GMT
Sender: netnews@pt.cs.cmu.edu
Lines: 15
In-Reply-To: <1648@runx.ips.oz>

In article <1648@runx.ips.oz>, brucee@runx.ips.oz (Bruce Evans) writes:
}much better. I still don't think acceptable throughput (== 19200 baud
}on a 5MHz 8088 with no load) can be attained without "fixing" the
}kernel. The problem is that interrupts are disabled for several
}millisec. I get about 4800 baud with lots of kernel changes.

I would suggest adding support for the 16550 UART in tty.c.  This chip,
which is pin-compatible with the 8250 and 16450, has a 16-byte on-chip
receive buffer, so an incoming 9600-baud data stream need only be read
60 times per second to prevent data loss.

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