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  • 48K banked memory

    From robc638@robc638@startmail.ca (Robert C.) to comp.sys.apple2 on Sunday, October 03, 2004 20:48:20
    From Newsgroup: comp.sys.apple2

    Answering Rob Jones' question, "A Solid-State Drive for the ][+" (see
    question somewhere on this Board), I got thinking about a way of
    bank-switching 48K blocks on the Apple 2 plus.

    My idea is to make banks of memory that would duplicate the main
    memory and switch it as necessary. Since the board could reside in
    slot 0, I would need to write a short ML subroutine that would poke
    the bank number into a slot specific address for slot 0. Logic would
    then intercept the address for main memory and redirect it to the
    selected 48K bank. This short program would need to be stored in a
    small ROM on the Ram Card.

    Looking closely at a 16K Microsoft RamCard that I have, I notice that
    it has no Prom. Exactly, how does the Apple know when to switch
    between the ROMs and the 12K+4K on the board?

    I can handle the hardware portion fairly easily, but I would need some
    help from advanced programmers to write the ML subroutine.

    Thank-You
    Robert.
    --- Synchronet 3.18b-Win32 NewsLink 1.113
  • From Paul R. Santa-Maria@paulrsm@buckeye-express.com to comp.sys.apple2 on Monday, October 04, 2004 00:42:49
    From Newsgroup: comp.sys.apple2

    "Robert C." wrote:
    Answering Rob Jones' question, "A Solid-State Drive for the ][+" (see question somewhere on this Board), I got thinking about a way of bank-switching 48K blocks on the Apple 2 plus.

    If you do that then you will end up with yet another incompatible-with-everything-else memory expansion.
    If you are doing this for fun, then go for it. However,
    if you are just trying to make a RAM drive for the II+
    then you are better off with a Slinky or a Saturn card.

    The Saturn card does bank-switching with the 16KB
    lanugage card area. The 128KB card gives you eight
    16KB banks. This method appeared to be the new
    memory expansion standard for the Apple II until the
    Apple IIe came out with its new bank-switched memory
    scheme.

    The Slinky card holds a megabyte of memory, but it can
    only be used for data storage. It is impossible to
    run code in the Slinky memory.

    One of the early Apple II memory expansion schemes was the
    Cramapple modification. It replaced the 16KB RAM chips
    with 64KB RAM chips and selected the bank using the game
    port annunciators.

    ************************************************************
    --
    Paul R. Santa-Maria
    Monroe, Michigan USA
    --- Synchronet 3.18b-Win32 NewsLink 1.113
  • From robc638@robc638@startmail.ca (Robert C.) to comp.sys.apple2 on Monday, October 04, 2004 08:52:26
    From Newsgroup: comp.sys.apple2

    "Paul R. Santa-Maria" <paulrsm@buckeye-express.com> wrote in message news:<4160D4C9.A2D862F8@buckeye-express.com>...
    "Robert C." wrote:
    Answering Rob Jones' question, "A Solid-State Drive for the ][+" (see question somewhere on this Board), I got thinking about a way of bank-switching 48K blocks on the Apple 2 plus.

    If you do that then you will end up with yet another incompatible-with-everything-else memory expansion.

    One of the early Apple II memory expansion schemes was the
    Cramapple modification. It replaced the 16KB RAM chips
    with 64KB RAM chips and selected the bank using the game
    port annunciators.

    ************************************************************

    I read up on the Cramapple modification and you're right: to add more
    memory with no software to go with it is useless. As it is put in this
    website (http://linux.monroeccc.edu/~paulrsm/dg/dg11.htm),

    "Since lots of 256K expansion boards and lots of Cramapple
    modifications are being sold and there is absolutely NO
    commercial software, where does that leave us? It leaves us
    with a lot of unusable RAM, that's where it leaves us!"

    OK, Scrap that project.

    Now, if someone could direct me towards a method of adding a better
    storage device, such as a Hard Drive, for the Apple ][+, I would
    appriciate it.

    Robert.
    --- Synchronet 3.18b-Win32 NewsLink 1.113
  • From Wayne Stewart@waynes@telus.dotnet to comp.sys.apple2 on Monday, October 04, 2004 17:02:22
    From Newsgroup: comp.sys.apple2

    Robert C. wrote:

    Now, if someone could direct me towards a method of adding a better
    storage device, such as a Hard Drive, for the Apple ][+, I would
    appriciate it.

    Lots of choices there. An Apple Rev C SCSI card works with a II+.
    So will a Hi-Speed SCSI card if you turn DMA off. The CFFA card now
    works with a II+. The RamFactor can use a battery backup and be
    partitioned into multiple volumes for DOS3.3, CPM, Pascal or ProDOS.
    The Sider and Vulcan drives can be formatted and partitioned for most
    Apple II formats. There's also lots of cards that'll work as a RAMdisk.


    Wayne
    --- Synchronet 3.18b-Win32 NewsLink 1.113
  • From Paul R. Santa-Maria@paulrsm@buckeye-express.com to comp.sys.apple2 on Tuesday, October 05, 2004 01:20:14
    From Newsgroup: comp.sys.apple2

    "Robert C." wrote:
    "Paul R. Santa-Maria" <paulrsm@buckeye-express.com> wrote:
    One of the early Apple II memory expansion schemes was the
    Cramapple modification. It replaced the 16KB RAM chips
    I read up on the Cramapple modification and you're right: to add more
    memory with no software to go with it is useless. As it is put in this website (http://linux.monroeccc.edu/~paulrsm/dg/dg11.htm),

    Hmmm. You are looking at my web site to confirm something
    I told you. I am telling the truth, but still...

    Now, if someone could direct me towards a method of adding a better
    storage device, such as a Hard Drive, for the Apple ][+, I would
    appriciate it.

    Do you want to buy something or build something?

    If you want to build a hard drive controller, then I
    recommend an IDE interface. You can find schematics at http://s.guillard.free.fr/Apple2IDE/Apple2IDE.htm

    --
    Paul R. Santa-Maria
    Monroe, Michigan USA
    --- Synchronet 3.18b-Win32 NewsLink 1.113
  • From robc638@robc638@startmail.ca (Robert C.) to comp.sys.apple2 on Tuesday, October 05, 2004 06:17:02
    From Newsgroup: comp.sys.apple2

    "Paul R. Santa-Maria" <paulrsm@buckeye-express.com> wrote in message news:<41622F0E.90C8E7FE@buckeye-express.com>...
    "Robert C." wrote:
    "Paul R. Santa-Maria" <paulrsm@buckeye-express.com> wrote:
    One of the early Apple II memory expansion schemes was the
    Cramapple modification. It replaced the 16KB RAM chips
    I read up on the Cramapple modification and you're right: to add more memory with no software to go with it is useless. As it is put in this website (http://linux.monroeccc.edu/~paulrsm/dg/dg11.htm),

    Hmmm. You are looking at my web site to confirm something
    I told you. I am telling the truth, but still...

    I had no idea it was your website. I plugged 'Cramapple' into 'Google'
    and it returned your site as the only hit.


    Now, if someone could direct me towards a method of adding a better
    storage device, such as a Hard Drive, for the Apple ][+, I would
    appriciate it.

    Do you want to buy something or build something?

    I enjoy tinkering with electronics, so I would prefer to build it
    myself.


    If you want to build a hard drive controller, then I
    recommend an IDE interface. You can find schematics at http://s.guillard.free.fr/Apple2IDE/Apple2IDE.htm

    I have seen his website. 7 chips to run an IDE / ATA HD on an Apple:
    easy enough! I just have a hard time understanding his logic board
    without the use of some sort of ROM to load the disk routines. Unless
    ATA will load the routines from the disk upon booting. Maybe one of
    you guys would lead me in the right direction.
    --- Synchronet 3.18b-Win32 NewsLink 1.113