ggibeau@ucqais.uc.edu (George Gibeau) (07/25/89)
The following is an article published by Greg Tibbs (who as reported
by Marco Pappa) is doing a hack to use the new OBESE Agnus (1 meg chip
ram) on the 1000. Greg is president of a local computer club. He has
a prototype running and will probably demo it at our next meeting (OVAUG).
***************************************************************************
The Amiga 1000 Upgrade Project by Greg Tibbs
Commodore has been working on what is called the enhanced chip set - an
improved Agnus and Denise chip which adds several new capabilities
to the Amiga. Unfortunately, the Agnus chip used in the A500 and A2000
is different from that in the A1000. Since the new Agnus allows the
machine to have up to 1 megabyte of Chip (graphics) RAM, it effectively
means the A1000 is obsolete.
Well, I heard all the yelling of people at CBM and decided to try
adapting the chip. I worked out a design and have a prototype
PCB that works. The following is a description of the project
called the Rejuvenator!:
1 I plan to create a daughterboard which replaces the A1000 WCS
(Write Control Store). It will be larger as it will include standoffs
for the Agnus, Denise, and Paula chips. Even so, the layout will be
made to minimize conflict with existing internal expansions.
2) It will require 8 256Kx4 Dram chips to yield 1 Mbyte. The way
!CAS is handled on the motherboard prevents it from being used with
the new chip. However, by raising Denise and Paula, along with
the new fatter Agnus, the old 512K chip Ram can be easily made
into 512K of Fast Ram at C0000H (so it will Autoconfigure). For
those of you with Spirit boards, provision will be made for addresses
or to disable the old chip RAM completely to prevent conflicts.
3) Because the WCS will be removed, there will be a socket for the
CBM A500/A2000 style ROM with extra addressing pin supported for
the time that CBM goes to 512K byte ROMS. This might require a PAL
change, but no rewiring.
4) Two jumpers determine the behavior of the board; One selects WCS/or
ROM. If WCS is selected, the motherboard RAM becomes 256K fast RAM,
addressed at 0F80000H, and 256K Kickstart RAM. If WCS is not selected
then the 1.2 or 1.3 ROM will be activated. The remaining two jumpers
will determine the address of the 512K RAM. For persons having
performed the 1 meg motherboard RAM piggyback upgrade, two of the
4 addresses specifically address 1 Megabyte of fast RAM.
5) The OKI clock chip that CBM uses in the A500 and A2000 is supported.
6) If 1 through 4 are implemented, the A1000 will have 512K of
Chip and 1 Meg of Fast, the 1.3 ROM, and the battery backed clock
chip. Since all decode logic will be PAL-based the timings should
be the same as on the old A1000.
7) This project will also have a minimal A2000-style video slot.
It will be a subset of the A2000's due to lack of Audio and parallel
port access. The Rejuvenator's video slot will run MicroWay's
FlickerFixer with no modifications or additional wires from the
motherboard. There are provisions for up to 11 jumper wires to the
motherboard to supply signals for the video slot if they are needed.
8) Through careful and ingenious design, there are *NO* trace cuts
on the motherboard. For basic operation, only two jumper wires are
required to connect to the motherboard. These are the 28 MHz clock
and a clock synchronization reset pulse. The OKI clock chip will
require an additional jumper wire to obtain the necessary 12 volts.
9) A socketed PCB (no chips) and a separate chip kit will be made
available to avoid FCC problems.
10) Hopefully, I'll have the prototype at the meeting to show it off.
-Greg Tibbs
*************************************************************************
I will post a message as to how it works if he demos it at our
meeting this Tuesday (the 25th). He will probably be making
this available as a LUCAS type project (shareware hardware).
Greg is on BIX, not sure of address, but I can pass along any interest
to him. He will also be at AmiExpo in Chicago and hopes to have a working
model with him to show off. I will be there too, so look for a large
group of loud folks from Ohio :-).
George Gibeau
--
Definition of HELL - A room full of MACS with all the right software
............on 5.25" disks ;-)
UUCP: ucqais.uc.edu!ggibeau BBS: (513) 721-7977 GT NODE: 006/005
US Snail-Dept of Biology ML 06, University of Cincinnati, Ohio 45221anakin@gpu.utcs.utoronto.ca (Anakin Research) (07/25/89)
Greg Tibbs BIX address is gbtibbs. I congratulate Greg for doing the impossible. By the way he says that he should have something ready in 60-90 days. My orders already in. Brad Fowles The LUCAS Project anakin@utgpu
portuesi@tweezers.esd.sgi.com (Michael Portuesi) (07/26/89)
In article <1989Jul25.160223.15544@gpu.utcs.utoronto.ca> anakin@gpu.utcs.utoronto.ca (Anakin Research) writes:
Greg Tibbs BIX address is gbtibbs. I congratulate Greg for
doing the impossible. By the way he says that he should have something
ready in 60-90 days. My orders already in.
Brad Fowles The LUCAS Project
Your order is already in? Can we place orders now? How?
Could anyone speculate on the odds of the Obese Agnus daughterboard
working reliably with a Lucas board in an A1000?
--M
look! a signature!
--
Michael Portuesi Silicon Graphics Computer Systems, Inc.
portuesi@SGI.COMggibeau@ucqais.uc.edu (George Gibeau) (07/26/89)
Just left our users club meeting where Greg Tibbs has demoed his
Rejuvinator card. (see previous posting as to particulars). He
brought a stock A1000 with his card in it and gave a very impressive
demonstration. The machine booted up to the workbench screen (had 1.3
ROM on card), was running with Obese Agnus chip just fine, showed off
video slot that will accept Flicker Fixer or other video cards, had 1 meg
ram on the card plus the 256 on the motherboard (this was running with NO
front panel 256K memory expansion cartridge), Commodore OKI clock, and
a few other goodies (it even ran Diga :-)). Board layout very impressive,
2-layed board. Takes up slightly more space than the present daughter
board. WILL work with the likes of the Spirit IN1000 memory card.
Greg said he will probably sell as a kit, but is unsure of the price
as of yet, but it will definately be an affordable way to continue
to upgrade the 1000.
He will be at AmiExpo with working machines and boards, so if interested,
look for him up there (hanging with the guy in the Australian looking
hat with the Grateful Dead pin on it - me :-))
I think this will be a great benefit to those of us that still own
1000's and do not really want to buy a new machine.
Will keep posting as results develop as Greg does not have access to
UseNet (but he is on BIX).
Regards,
George Gibeau
Vice-PResident
Ohio Valley Amiga Users Group (OVAUG)
--
Definition of HELL - A room full of MACS with all the right software
............on 5.25" disks ;-)
UUCP: ucqais.uc.edu!ggibeau BBS: (513) 721-7977 GT NODE: 006/005
US Snail-Dept of Biology ML 06, University of Cincinnati, Ohio 45221anakin@gpu.utcs.utoronto.ca (Anakin Research) (07/28/89)
>>In article <1989Jul25.160223.15544@gpu.utcs.utoronto.ca> anakin@gpu.utcs.utoront >>o.ca (Anakin Research) writes: >> Greg Tibbs BIX address is gbtibbs. I congratulate Greg for >> doing the impossible. By the way he says that he should have something >> ready in 60-90 days. My orders already in. >> >> Brad Fowles The LUCAS Project >> > >Your order is already in? Can we place orders now? How? > >Could anyone speculate on the odds of the Obese Agnus daughterboard >working reliably with a Lucas board in an A1000? > > --M > >look! a signature! > >-- >Michael Portuesi Silicon Graphics Computer Systems, Inc. > portuesi@SGI.COM Michael, I don't know if Greg is formally taking orders. I have talked with him on BIX and told him that I want one soon as they are available. Unless there are some surprises the LUCAS/FRANCES combination should work with Greg's board. There may be a form factor conflict but since the LUCAS board only connects to the AMIGA via the 68000 socket, we should be able to insert a 64 pin machine socket or two to clear Greg's board. If for some reason it doesn't work, I will spend considerable time devising a hack to make it work. I've grown quite fond of my 1000 and 1 meg of chip ram is an irresistable hack. Brad {. {.
rickf@pnet02.gryphon.com (Rick Flower) (07/28/89)
Personally, my A1000 is DEAD until I either get a new daughterboard OR perhaps this new-and-enhanced daughterboard.. I'd personally like to know the specs on it (which I don't recall seeing here on the net, but I might have missed something! (:->) ) and a wild ballpark guess on a price... +-----------------------------------------------------------------------------+ | Caution, Assembly Language Programmer at Play! | | | | UUCP: {ames!elroy, <backbone>}!gryphon!pnet02!rickf | | INET: rickf@pnet02.gryphon.com | +=============================================================================+