HM> Presumably this would only work for fossil applications,
 HM> though?

yeap..

 HM> WC> hope that explains it. BTW System Manager uses its own serial ports
 HM> as
 HM> WC> there is no real IBM standard above 2 yet..

 HM> Well, COM3 and COM4 have standard addresses but not
 HM> standard non-conflicting IRQs. Would SM support a Digiboard

still not IBM  standard :-)

 HM> or other intelligent (or dumb) serial board?

why bother it comes with its own ( all required hardware ) when needed.  
 
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