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- A3000 Kickstart ROM Procedure
-
- This document describes how to create your own 2.04 (or later)
- ROM-based A3000. It entails procedures & modifications that you may need
- to make to your A3000. It requires the A3000 superkickstart disk and
- two 200 nanosecond or faster 27C220 EPROMS. For obvious copyright reasons,
- I cannot distribute the actual kickstart ROM images, but the program
- ROMSPLIT or ROMSPLIT1 will create the images from your A3000 which
- most eprom programmers can read.
-
- The next question is why create EPROMS? Well, 68040 cards for the A3000
- require 2.0 in ROM. These cards are ready and shipping but A3000s
- with 2.0 in ROM aren't shipping yet. With this procedure you can make
- copies for yourself in a legal manner. Developers can use their
- 040 machines to test newer betas (beyond 2.04) without having to pull
- out their 040 cards. The reason the superkickstart process fails on
- 040 cards is that the kickstart ROM image is remapped into fast ram
- via the MMU. The 040 MMU is different enough from the 030 MMU that
- the bootroms crash.
-
- The programs ROMSPLIT and ROMSPLIT1 are hereby released to the public
- domain with no distribution restrictions whatsoever.
-
- WARNING! Performing these procedures will probably take your A3000 out
- of warranty. Please carefully read the instructions completely and
- do not start until you thoroughly understand the process.
-
- 1) A3000s have four ROM sockets. Only two are used in any one machine. Most
- A3000s have special bootroms which load kickstart 2.0 and 1.3 from
- disk. These ROMs must be pulled. Earlier A3000s used 27C220s, later
- ones use masked ROMs, with each tpe using a different pair of sockets on the
- A3000 motherboard. The four ROM sockets are located on the motherboard
- along the right-hand side of the A3000. The first (front) two are for the
- Masked ROMs,the second two are for EPROMS.
-
- 2) Unfortunately CBM started to not solder the EPROM sockets into the
- most current A3000s although the traces and holes are there. To use these
- machines, you must unsolder the holes, put in a 40 pin socket and perform
- a decent soldering job. To effectively desolder the motherboard holes for
- EPROM sockets, you must remove the motherboard. A temperature controlled
- grounded tip desoldering station is strongly suggested. In soldering on your
- A3000 motherboard, you will definitely void warranty and you perform this
- procedure ENTIRELY AT YOUR OWN RISK!
-
- 3) By running the Update2.x program on your A3000 install disk, put the
- kickstart image for the version of the ROM which you want onto your
- disk. It will be called kickstart and located into your devs: directory.
-
- 4) Depending on your EPROM programmer, run ROMSPLIT or ROMSPLIT1. These
- programs read the devs:kickstart file and create two binary output files
- called Kickrom0 and Kickrom1. ROMSPLIT stores the image in order as read
- by the 68030 processor. ROMSPLIT1 performs byte shuffling required by the
- Intel processors. My BP Microsystems EP-1140 programmer requires that
- ROMSPLIT1 be used. I suspect that most programmers will want Intel
- byte ordering, but I included both programs just in case.
-
- 5) Copy Kickrom0 and Kickrom1 files to your EPROM programmer. Use
- CrossDos, or Lharc the files and use a telecom program, use whatever works.
- On the EP-1140, I use CrossDos and a 720K formatted diskette to put the
- files on my 386PC. I then load the programmer software, select
- INTEL 27C220 and load binary file. Note that some programmers may not
- load binary files. Most do.
-
- 6) Program the EPROMS.
-
- 7) Take the EPROMS and put them into the last two ROM sockets (The furthest
- two ROM sockets from the front of the A3000. Note that Kickrom0 corresponds
- to ROM0 and Kickrom1 corresponds to ROM1. If your A3000 had EPROMS, read
- the label. It usually identifies which ROM goes where. If not, look at the
- silkscreen. It identifies ROM0 and ROM1. Be careful of PIN 1 orientation!
- Make sure all pins go into the sockets.
-
- 8) Make sure that if your A3000 has masked ROMs that you pull them out of
- their sockets; there should only be two ROMs or EPROMs in the machine at a
- time.
-
- 9) Put the A3000 back together. Power up. Note that the A3000 daughtercard
- must be installed for the system to work. If the machine doesn't come up,
- recheck ROM installation. Try swapping the two ROMs (The silkscreen may
- be wrong on Rev 7 motherboards). In worst case, put the original bootroms
- back in and see if you can boot. Perhaps you can reprogram using the
- opposite program (ROMSPLIT versus ROMSPLIT1), which generates different
- EPROM binary files.
-
- 10) At this point, the machine is running 2.0 in ROM.( You could possibly
- do 1.3 as well!!) This procedure has been tested with 37.175 and newer
- beta versions and found to work in these cases.
-
- 11) For more performance, you can obtain faster 27C220 EPROMS. 150 nsec
- speed Eproms will allow you to play with jumpers (see your A3000 manual)
- to cut out a few wait states. Generally, put the ROM speed jumpers in the
- 16 Mhz position.
-
-