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FRAM71 1MB Issue - Printable Version

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FRAM71 1MB Issue - Dave Frederickson - 02-21-2016 10:28 PM

If you have a 1MB FRAM71, consider that the 16K built into the 71 is shared between the Top and Bottom configurations. If you have files loaded in :MAIN that reside in the built-in RAM in one configuration and clear memory in the other, guess what? The files in the first configuration are gone and the file chain is probably corrupt. My recommendation is to FREEPORT the built-in memory if you have a 1MB FRAM71. This goes for plug-in modules, as well, which can be used to transfer files between the Top and Bottom FRAM's.


RE: FRAM71 1MB Issue - Sylvain Cote - 02-22-2016 12:54 AM

Hello Dave,
Never thought about it but it make perfect sense.
All my FRAM71 modules are 1MB so I will do some experiments when hobby time will become available again.
Thanks for the tips.
Best regards,
PS: the 71B compendium is still progressing, but at a glacial pace. I should be able to publish a significant update somewhere in march.

RE: FRAM71 1MB Issue - Dave Frederickson - 02-22-2016 02:00 AM

Hi Sylvain,

Most users will have configured a large amount of RAM, after all, that's what FRAM71 provides. The memory allocation routine will assign the larger memory blocks first, and the 4K blocks will be assigned last, consequently one would need to use up most of :MAIN RAM before using the 4K blocks. That's probably why no one has reported this issue.