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From: mouth@ibm.net (John Kelly)
To: Bruce Evans <bde@zeta.org.au>
Cc: hackers@FreeBSD.ORG
Subject: Re: Status of 650 UART support
Date: Sat, 15 Nov 1997 00:53:49 GMT
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On Sat, 15 Nov 1997 00:53:34 +1100, Bruce Evans <bde@zeta.org.au>
wrote:

>interrupts need to be reenabled on the polled ports as soon as everything
> in them is polled

Only if your clock interrupt is too slow.  But I wanted to change that
and leave the UART in polled mode after draining it.  Only after 5
polls with no data would I switch it back to interrupt mode.  Then the
serial ISR could ignore all ports being polled.

>The next clock interrupt is an average of 5 msec away

Would it be feasible to tick the clock every 1ms to schedule UART
polling and on every fifth tick run the usual kernel scheduling?

John