Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!ANDREW.CMU.EDU!jm7e+ From: jm7e+@ANDREW.CMU.EDU ("Jeremy G. Mereness") Newsgroups: comp.sys.apple Subject: Re: Extended 80-Col. on //e Message-ID: Date: 13 Jun 88 21:38:06 GMT References: <8806111237.AA19491@crash.cts.com> Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 38 >From: Joe Burke >Is there anyway to use the extended memory of the Extended 80-col card with >the regular memory? Thanks. The 65c02 in the Apple //e can only address 64K of memory at a time. in order to use any extended memory, you have to perform what is known as bank-switching where the machine litererally swaps one 64K bank for another. This can be a problem, as just routines must exist in each bank of 64K to take care of itself when you make the switch. It's a mess, and cards like RAMWorks, which are simply extended 80-column cards multiplied over a few times, only make it worse. However, Prodos has routines that can handle extended memory. Appleworks is a brilliant example of how a large program can use Prodos routines to fit itself within the tiny 64K space the 65c02 allows. What is done is the program is segmented and Prodos handles the memory switching. Check out Appleworks running under a 512K Ramworks (eight 64K banks) with AE's enhancements that put all of Appleworks into a RAM, still manages to enlarge the desktop (the Appleworks desktop is handled by Prodos routines (I think) and kept in extended memory) and also provides a print buffer; a feature unique to RAMWorks. No other Ramcard can feature a print buffer. I do not think GSRam or slot 1-7 cards are capable of it. Obviously, I do not know how this feature can work, and Applied Engineering isn't telling. I hope this gives you an idea as to what you can and cannot do with extended memory. If I had my way, I would have a //e with 512K extended to hold a huge desktop/print buffer and then have an additional 512K in a slot 1-7 card to act as a RAM disk. But that takes money and another slot... Capt. Albatross jm7e+@andrew.cmu.edu ============ disclaimer: These opinions are mine and will remain so until more intelligent or insightful or informed people are kind enough to show me the error of my ways. Remember: A mind is a terrible thing to baste.