Brian, Absolutely not. JOS would have to be fully ported to work without the SuperCPU. It is HEAVILY dependant upon 65816 features not present in the 6502 CPU. It relies upon these features to do multitasking. LuNIX, however, already runs on a 6502. It will probably run straight off. The only reason to even mess with it would be to take advantage of the advanced hardware of the J-board (sorry Jeri.) From what I understand of LuNIX, that ought to be pretty easily done. I don't think Jeri has yet specified how the extra memory is addressed. I suppose the simplest route is to have it bank switched. If you think about it, there's no reason to invent an entirely new standard for something like extended addressing when one already exists. If the 16Mb RAM is bank-switched, it would make sense to use a scheme compatible with the C-128 banking scheme. Just expand the MMU registers to their full potential, giving us RAM0-RAM255. This will work toward eventual C-128 OS compatibility and programmers already understand it well enough. Of course the MMU will have to be further modded to ensure it can remain mapped into the system under the C-64 configuration. Should not be a problem if we're creating the new MMU in digital logic rather than silicon anyway. In this scheme, its almost like having 24-bit addressing, except that the MMU controls the upper 8bits of the addy buss. Another cool benefit of going this route is that it gives the C-64 environment access to the other features of the MMU such as relocateable stack and Zero Page. That would be excellent for people doing multitasking projects :) I don't see any point in trying to emulate a 16Mb REU with the on-board RAM. We can always build a SEPERATE 16Mb REU to be added later ;) In the end though, I suppose there's nothing to stop Jeri from simply adding 8-bits to the addy buss and controlling it with her own logic either inside or outside the emulated 6502. It's her project after all. --- Bryan Pope <email@example.com> wrote: > Oh right... Hmmmm... But J-board is supposed to > come with 16MB. > So then the new CPU has 24 address lines or does > bank switching. > Now since the CPU is running a lot faster then a > stock CPU (and > uses 24 address lines) JOS should be happy (Except > for any 65816 > specific code) ===== Get a FREE 6Mb webmail box from go6502! - http://www.geocities.com/profdredd As low as 2.99% Intro APR from NextCard! - http://www.nextcard.com/index6.html?ref=aff0074521 PayPal is the FAST FREE and SECURE way to send money! - https://secure.paypal.x.com/refer/pal=profdredd%40yahoo.com __________________________________________________ Do You Yahoo!? Yahoo! Auctions - buy the things you want at great prices http://auctions.yahoo.com/ - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail firstname.lastname@example.org.
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