Re: [NTLK] Source for DIL switches

From: Robert Locatelli (sickofthecrap_at_mac.com)
Date: Sun Jul 28 2002 - 08:54:29 EDT


Am 28.7.2002 14:12 Uhr schrieb "Bernie A. Goltermann" unter
<bagoltermann_at_ksaits.com>:
> I thought of that as well but it's more
> elegant to have a 3 pole switch.
Of course, Bernie, you're right. We need a changeover in case of direct
switching. However, there will be an uncertainty during the switching that
none of the switches is closed and the MP crashes just then. I think someone
reported that his solution with a changeover switch failed sometimes.

In earlier uP-times (Z80 and the like) we had to worry about any single
cycle because it was needed to refresh the DRAM. Therefore we built a small
D-flip-flop circuit and could switch w/o any risk. Space would be enough in
the MP2100...

-- 
With best Regards / Viele Gruesse!

Marco Mailand

http://slsbd.psi.ch/timing http://slsbd.psi.ch/~mmailand/ https://www.paypal.com/refer/pal=YYD3VUXUVD2YG

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