Conference hydra::amiga_v1

Upgrade: (what my roommate did)


              1. Buy an Amiga 500
              2. Sell C64

There is no way to make a C64 *into* an A500.



Dragons Lair takes 1.5 MEG?!?!?!?!
Your best off adding the internal RAM first since it can later be used a CHIP
RAM with that sow, AGNUS.


A500 2MEG internal from C-A?  Sounds good to me!

John

    Twice this year Commodore has offered generous tradein deals.  The
    first was Amiga 1000 + $1000 = Amiga 2000.  The second, which expired
    either at the end of September or just days ago, gave $few hundred
    credit for a C-64 tradein or $1000 credit for an A1000 toward an
    A2000.  I think there may have once been a program to trade in C-64s
    towards the A500.
    
    No doubt this will happen again, especially around Christmas.  Keep
    your eyes open for it.

    Commodore had an offer in September that allowed a $100 trade-in
    on ANY old Commodore machine toward an Amiga 500 or 2000.  Rumor
    has it that the offer was extended to December 31.

    
    	I was at OMNITEK in Salem 3 weeks ago.
    	The person there, who did not seem to really know their products
    	 told me that I could get $50 for either a VIC-20 or a C64 on
    	 a trade-in for an A500 or $100 for an A2000.
    
    	This person told me this was a special deal that Omnitek was
    	itself was doing, that Commodore was no longer running a trade-in.
    
    	There does seem to be a fair amount of confusion out there....

    When I bought my son's A500 in September, the dealer (Maryland)
    told me that $100 was the trade in credit for a C64 in *ANY* condition
    (it did not have to work). I'm not aware that the offer was extended.

Re: .0

The rumor about Commodore switching to 1 megabit RAM chips is interesting.
I will make a prediction:

	Within 6 months, Commodore will switch from 256k RAM chips
	to 1 megabit RAM chips in both the Amiga 500 and 2000.

This is an easy prediction: 256k RAM chips are increasingly hard to
get and expensive.  1 megabit RAM chips are increasingly easy to get
and less expensive than 256k chips.  Yes, it is cheaper to buy one 
1 meg chip than four 256k chips.  Since using 1 meg chips decreases
manufacturing costs (four times less chips to place on the board)
and decreases power consumption, 1 meg chips are the way to go.

Those of you that follow the Apple computer market heard about the
new Mac II+.  It is a rushed out the door 68030 machine (its major
job was to get Apple a position in the '030 market before NeXT
introduced their new machine).  About the only change in the Mac II+
besides the '030 was that Apple modified the mother board to use
1 megabit chips.  Apple has had to curtail production slightly
in recent months because it could not get enough RAM to build systems.
(A few contracts for a large number of Macs were in danger of not being
satisfied!)  Apple, always putting the best light on things, claimed
that demand for the Mac exceeded Apple's  ability to produce them.
A true statement, but it is because production is down, not that
demand it up.

Back to Amigas:

Using 1 meg chips has an interesting consequence:  the smallest about of
memory that you can supply is one Megabyte.  Each chip delivers one meg
of bits.  The cheapest way to get a byte is to use eight chips in parallel:
each chip produces one bit in the byte.  Thus, you get a minimum of one
Megabyte.

Both the Amiga 500 and 2000 have one Megabyte (the 500 does require the
memory/clock expansion to get to this configuration).  However, the
meg of memory is in two separate 512K byte chunks.  One starts at address 0;
the other at address C000000 (give or take a zero or two :->).  The problem
is that such a configuration isn't the most natural way to use one meg
made up of eight 1 meg chips.  The most natural way to use the memory is
as one contiguous block of memory.

This brings you another interesting point:  there is more to a computer's
memory than the RAM chips themselves.  Various memory support functions
need to be handled (address decoding, refresh, ...).  In for expansion
memory of the Amiga, those support functions are handled by additional
chips on the expansion board.  For the Amiga motherboard, those functions
have been pushed into the Agnus chip.  (The 512K + clock expansion for
the Amiga 500 counts as being on the motherboard for this discussion.)
The current Agnus chip handles a total of one megabyte of memory in
two separate "chunks."  Only the chunk at address 0, can be used as chip
memory.  Commodore has announced that they are working on a new Agnus
chip that handles the 1 Megabyte of motherboard memory as one chunk with
all of the megabyte being chip RAM.  The new Agnus is the furthest along
of the revised chipset for the Amiga.  At the Developer's conference in
April, Commodore distributed samples of the new chips.  Fred Fish was
awarded with one of the new Agnus chips because of his contributions
to the Amiga community.  Unlike the other new special chips, the new
Agnus requires no software changes to use: Kickstart probes memory
when the machine is turned on to determine the amount of chip RAM,
and whether there is any RAM at C000000.

I think see where these two lines of thought are going.  At some point,
Commodore will switch over to a new Agnus and 1 megabit chips at the
same time.  This may occur without having to update the rest of the
custom chips or the operating system.

I predict that in the future that both the Amiga 500 and 2000 will
come with 1 Megabyte of chip memory standard, and that the memory
will be made up of 1 megabit chips.

I doubt that either the 500 or 2000 will be updated at that time to
come with two Megabyte of memory standard.  To do so would require
adding additional memory support to the motherboard (Agnus can only
support 1 megabyte of memory).  So, this will not happen for awhile
yet.

Note that Commodore's switching to 1 megabit chips does not effect the
usability of the new Agnus in existing 500s or 2000s.  You will still
be able to use the Agnus chips.

Also note: I've pulled the same trick that most psychics do.  Make a
specific but undetailed prediction up front ("Commodore will switch to
1 megabit chips in 6 months")  followed by a less specific but more
detailed prediction ("Commodore will switch when they release the
new Agnus chip").

So, if Commodore switches to using higher density memory chips in the
next six months, I win.

So, if Commodore takes a year to switch but ties the switch to the new
Agnus, I win.

So, if Commodore take over a year to do anything, everyone will have
forgotten what I said, and I don't lose.

    There's a bit of a hole in .6:
    
    If you're dealing with 1MB by 1 bit chips, and the data bus is 16
    bits wide, the minimum increment would involve stringing 16 chips
    in parallel, giving you 2MB of memory.  If, as .6 suggests, you
    just put 8 together in parallel, you do indeed have 1MB of memory,
    but since the 68000 does things 16 bits at a time, I'd think you'd
    have to cycle memory twice to get 16 bits out of an 8 bit wide memory
    (which would seem to slow things).
    
    Or, is this what they already do?

    re: 1 meg chip predictions
    
    Just curious, I remember when the 16K chips were first coming out,
    companies would use 8K chips that were actually failed 16K chips
    that only had 8K good.
    
    I assume there are failed 1 Meg chips, is it possible that there
    will be failed 1 Meg chips with 512K good?  At a price cheaper than
    good 1 Meg chips?  (I've never heard of any, but it makes a great
    rumor).  If true, that still reduces the number of memory chips
    needed by half.  Two banks of them would give you one meg,
    and an easy way to get to two meg by replacing them with real
    1 Meg chips.
    
    -Dave

    
    re: OmniTek
    
    I have an ad from them that says:
    
    Attention all commodore owners!
    Trade in your old computer towards a new AMIGA 2000!
    AMIGA 500 or AMIGA 1000 and $1000 for an AMIGA 2000
    All other Commodore Computers $800 off
    C-64, Vic-20, C-16, Plus 4, SX-64, SuperPet, Pet, and C-128 are
    all eligible!
    Come in for a free demonstration!
    Ask for details
    Only one trade in per Amiga 2000
    
    Note the $800 off, I assume that means off the suggested list price,
    I believe that is now $2195.  Which probably translates to $100 off 
    their store price, so it should be around $1400.  But hey, what
    a great way to get rid of a Vic-20 :-)  I believe that offer runs
    until they run out of the current stock of A2000s.
    
    hmmm... I wonder if Atari dealers will do the same...
    Maybe if CBM dealers extended this deal to other Jay Miner creations
    like the Atari 400/800/xl/xe computers...
    
    -dave

Re: .7

Sigh.  After thinking about it, you are probably right.  I guess I left the
following case out of the end of .6:

"But, someone may find a flaw in this immediately, and I lose."

    	One Meg DRAMS also come as 256Kx4, so you have additional options
    in the way you can configure the memory banks.
    
    	This means that for a 16bit data bus, you can have four of the above
    and increment 512K bytes at a time. 
    
    Miguel A. Alvarez

Re: .12

I thought of 256k x 4 DRAMs, but they are more expensive, aren't they?