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Megabit 128 ROM Adapter review and pre-orders (fwd)

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Feb 26, 2009, 2:14:15 AM2/26/09
For the C128/C128D Internal ROM Socket
Developed by D. C. Newbury newbury(at)

Review by Mark R. Brown


The Megabit 128 internal ROM Adapter is a small circuit
board that plugs into the internal expansion ROM socket
on the Commodore 128 or C128D. Its purpose is to allow
you to use high-capacity EPROMS: 27010 (1 meg.),
27020 (2 meg.), 27040 (4 meg.), or 27080 (8 meg.).

It's very easy to install. Since the board is longer than a
standard EPROM, you have to bend down a couple of
small disk caps on the 128 motherboard before you
snap it into the internal ROM socket. There's also a
pigtail with a clip that has to be attached to a pin on the
U3 chip. Piece of cake. No soldering. Easily removed if
you need to.

Newbury currently sells two different versions of the
adapter board. One addresses up to 16K at a time; the
other addresses up to 32K at once. Each is the same
price: $15 PPD in the US. Each uses the same
EPROMs; which you choose comes down to how big a
memory space you need to have active at any one
time. The 32K version lets you include bigger apps,
like KeyDos, the Servant, and BASIC 8.


An even better deal than just buying the bare board is
to add five bucks and order either board with an
EPROM preprogrammed with some apps and a nice
menu program. This not only gives you a set of
useful apps right out the gate, it means non-technical
types can actually do something with this board.

Because if you want to do something of your own,
you're on your own. While the developer is a very
helpful guy, there's no easy way right now to get your
own apps up and running on this board. Here's what
he wrote back when I asked how to program my own
EPROM apps for this board:

"I will have to put something together, like a separate
manual that will have the commented ML listings for
the auto start routine, menu and program loaders. It
may take awhile."

Then he mentioned something about fishing.

Just remember that full support for developing your
own menus and apps is planned. It's coming.
Sometime. Also remember you're only paying $20
([domestic] shipping included) for the
preprogrammed edition of either version of this
little marvel. If it were $50 or more, I'd linger here
awhile, complaining. But for twenty bucks I think
that's more than fair.

Okay. Fine. So we're stuck for the time being
with the programs and menu system he's burnt
for us. So let's talk about that.

Because what's already included is a load and
a half.


When I turn on my C128 in 40-column mode
and press F1, nothing happens. At least,
nothing happens on my C128. It might be
interference with JiffyDOS, since I get the
JiffyDOS '@$' command with F1. I don't
know, but I'm not going to pull my JiffyDOS
chip to find out. Maybe it's just an 80-column
app. The manual doesn't make that clear. So
let's try 80-column mode.

Press F1 and... okay, THERE we go! A nice
menu of apps. What's available? Some of the
best, most-used C128 and C64 utilities.
Here's a list:

16K version w/4meg EPROM:
Merlin 128 v1.0
Promos 2.0
My Disk Editor
Function keys
Viza Write 128
Viza Star 128
Seq Reader 128
Begin & End Adrs
Fastrac File copy
Directory Editor
Color 80 column
Basic Data Maker
Monitor 64
Basic Merge
Basic Merge +
Maverick File Copy
Maverick Track Editor
Single 41 Data copy
Dual 41 Data Copy
Single Nybbler
Dual Nybbler
Single 81 Data copy
Maverick File Tracer
Maverick Track & Sector Editor
64K VDC RAM Test
REU Test

32k version w/1meg EPROM:
Key Dos
My Disk Editor
Seq Reader 128
Color 80 Col
Function Keys
Begin & End Adrs
BASIC Data Maker
BASIC Merge +

The 16k version is a melange of C128 and C64
apps, some commercial and some written by
Newbury. All are very useful. I can't imagine
there's much you'd want to do that isn't covered
in here somewhere. But, just to be contrary, I
do miss not having a disk cataloger and a
simple text editor like ZED.

When you pick a program it comes up in a flash,
of course. C64 programs kick into C64 mode
and run flawlessly.

The programs have not been modified in any
way that I can tell, other than to make them
work from the internal ROM. That means when
you're done using one of these programs, you
have to power cycle your machine to quit.
(Newbury's own programs do politely drop you
back into BASIC when you exit them.)

No problem, as long as you didn't expect this
thing to work like Partner 128, letting you
jump back and forth from applications to
utilities like Bond from babes to bomb blasts.
You can't have everything, dude.

You DID remember to save your program
before you hit F1, didn't you?


What other goodies do you get? For twenty
bucks? Are you kidding?

Newbury sent me a review package that
was complete with a printed manual and a
CD-ROM containing the documentation for
all of the programs on the EPROM. I doubt
you'll get all that for a couple of sawbucks.
But I assume he'll be making it all available
on the web for free.

Installation instructions are complete and
more than adequate to the (very simple)
task. The manual includes documentation
for all of the utility programs Newbury
developed himself. The CD-ROM has PDF
manuals and d64 files for all of the
commercial apps included.

As stated above, there is, as yet, no
documentation on how to create your own
EPROMs. But did I mention that it's


Best twenty bucks you ever spent. Ever.
Pawn your grandpa's watch and buy this
right now. Really. I mean it.

Though I desperately want to create a
menu and load it up with my own apps,
for twenty bucks what Newbury provides
is an excellent selection.

The board couldn't be easier to install.
If you can install an internal ROM, you
can install this board.

This is a fine product and it solves a
basic problem. At least it did for me.

I've already decided to keep the 32K
version installed permanently. I had
burnt EPROMs for KeyDos, the Servant,
and BASIC 8, and have been struggling
for a year over which of them to keep in
that socket. Now I don't have to choose.
Best of all, all three apps are 128-mode
programs; I hate having to switch to C64
mode to do anything. Now I don't have to.

[Dan Newbury, developer of the Megabit
128 Internal ROM Adapter, has more to
say about it.]

I did not mention... that the printed
manual is not included in the package....
It costs too much (ink, paper, cover
and postage). But, if you want to pay
extra for a printed manual, we could
work something out. The adapter will
come with a CD that has the manual in
pdf format and all the other goodies.

I did find a bug in the adapters after I
sent them... It’s a hardware problem,
not in the software. Sometimes when
you power up, the internal ROM will
not be on page 0. The F1 function key
will not get reprogrammed and you
can’t get access to the menu. You
have to power down and up to make
it work. The new 32k board will
correct the problem.

I accept paypal or money orders.

The DO IT YOURSELF manual will
take more time.



Feb 26, 2009, 3:25:19 PM2/26/09
Dan was kind enough to send me this little board for review, which I
did on the C128Alive! forums. It solved a simple but mind-numbing
problem for me: whether to keep BASIC 8, the Servant, or KeyDOS in my
C128's internal ROM socket. Now I've got all three, and they're
function-key selectable. If that's all it did, it would be more than
worth the $20 ppd. he's asking. Check out the specs above for
yourself. This is a sweet little product.

Feb 27, 2009, 7:03:14 AM2/27/09

Has this been tested with the SuperCPU by chance?



Feb 27, 2009, 3:42:13 PM2/27/09
On Feb 27, 4:03 am, Shaun wrote:

> Has this been tested with the SuperCPU by chance?

Not yet. :)

Robert Bernardo
Fresno Commodore User Group
CommVEx v5 info -
and click on ComVEX

Feb 28, 2009, 1:37:49 PM2/28/09
Mark Brown wrote:

> Each is the same price: $15 PPD in the US.

Postage Paid in the U.S. is no longer the case. Dan
Newbury says shipping and handling are *not* included.


Feb 28, 2009, 5:36:51 PM2/28/09
On Feb 27, 7:03 am, ""

<> wrote:
> Has this been tested with the SuperCPU by chance?

If I could get one for testing, I would be glad to. Meanwhile, I put
the manual up for anyone to view:



May 8, 2009, 8:25:00 PM5/8/09
On Thu, 26 Feb 2009 12:25:19 -0800 (PST), airship <>

Just got my yesterday, Installed perfect and works good. Press
"F1" and in a snap, the Menu pops up. Has some nice utils on it
as well. Check out the link below for a list of programs on the ROM.

Thanks Dan for making this baby. NICE...


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