[time-nuts] Leap Second quirk, Another hanging bridge

[Chris Kuethe]

On Tue, Aug 12, 2008 at 5:18 PM, Scott Newell <newell at cei.net> wrote:
> At 06:29 PM 8/12/2008, Hal Murray wrote:
>
>>USB isn't fundamentally evil.  It's polled, so you won't get great response
>>to something like a PPS interrupt.  But the polling is handled automagically
>>with modern hardware so It's not much worse (maybe better) than the typically
>>interrupt batching that RS-232 chips do.

Unless you configure your RS-232 chip to not batch interrupts...

> I wonder if using isochronous USB transfers would result in more
> consistent latency.

It'd probably suck less, but you still have a trip up and down the usb
protocol stack. And I haven't seen any usb-serial converters that do
control lines properly...

-- 
GDB has a 'break' feature; why doesn't it have 'fix' too?