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CMT 64Kb RAM module for HP-71b question
10-12-2021, 03:52 PM
Post: #30
RE: CMT 64Kb RAM module for HP-71b question
(10-12-2021 08:00 AM)J-F Garnier Wrote:  
(10-11-2021 09:26 PM)mfleming Wrote:  However (wait for it) the table is not cleared by a RESETX command.
Yeah, I was suspecting that :-)

J-F

Oh my, I may have spoken too soon. Although the mapping table isn't cleared directly in the RESETX command handler, when finished control is transferred to the Initialize Device routine that does clear the mapping table. It also enters a spin-wait for Daisy-In to go high, so bus commands will be ignored until the MultiMod is configured. I'll confirm this behavior is valid or not with a logic analyzer on the bus.

I've nonetheless made the call to the clear mapping table routine in the RESETX handler. The change has been pushed to the repository and Hex files also updated.

A workaround for the moment is to not enumerate the second 16KB ROM (Ulib52) in the default MultiMod configuration. Do so by POKE "2C000","1" rather than using a "3" to enable all ROMs. That seemed to work for polbit. Sylvain, could you check if this is true for one of your Memory Lost scenarios?

~Mark

Remember kids, "In a democracy, you get the government you deserve."
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RE: CMT 64Kb RAM module for HP-71b question - mfleming - 10-12-2021 03:52 PM



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