Date: Wed, 09 Apr 2003 16:31:08 -0700 From: Terry Lambert <tlambert2@mindspring.com> To: Harti Brandt <brandt@fokus.fraunhofer.de> Cc: ticso@cicely.de Subject: Re: realtime problem Message-ID: <3E94AD3C.B17D2751@mindspring.com> References: <20030409114957.GN83126@cicely9.cicely.de> <20030409160038.B658@beagle.fokus.fraunhofer.de>
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Harti Brandt wrote: > On Wed, 9 Apr 2003, Bernd Walter wrote: > BW>Well it's wishfull to have non failures on my requirements, but if it > BW>does fail once it is detectable and it only costs a small amount of > BW>money - noone will die because of it. > BW>If I would need garantied 100% acuracy, then I would spend the money > BW>into a microcontroller to do the job. > BW>In fact I need it for the programming impulse on writing EPROMs and > BW>GALs. > BW>GALs are the devices which may need a 1ms programming impulse, but I > BW>don't know if there are really devices on the maket which use 1ms. > BW>EPROMS are not very sensible on the programming length. > BW>I really hate that available burners need DOS or Windows. > > So that is really not a classical real-time problem. The above should > work. I still recommoned shoving HZ up by over a factor of 10, and the quantum down by a factor of at least 5 less than the precision required. That will (almost) guaranteed that you are always in a loose ballpark around your 1mS deadline, which should be less than 500uS. You may lose out once in a while, but it shouldn't bee too often (I assume the thing's not going to be exposed to the Internet ;^)). -- Terry
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