Commodore Free 11/Commodore_Free_Issue_11_2007_Commodore_Computer_Club.d64/t.iv jens 2

Text File | 2007-01-01 | 12.6 KB | 387 lines

u  Interview with Jens Schofield
         Individual Computers

 http://www.jschoenfeld.com/index.htm

PART 2 of 4

Q-Have you create., or participated in
the creation of, anything Amiga related
beyond Individual Computers?

A-Yes, I was involved in multiple other
hardware developments. The Hypercom
3plus & Hypercom 4plus cards are my
designs, because VMC has split with the
designer of the original Hypercom
cards, Karl-Werner Riedel. I made the
new "plus" cards in 1998, which solved
all problems that the old cards had.
Another design that's Amiga-related is
a replacement for a floppy drive called
"EZ-drive".
Eyetech has used these "silicon drives"
(that was the internal name) to start
an Amiga that is installed in a Kiosk
system. Another design that I made for
someone else is a USB card. I designed
it for Creative Development (CreDev),
but they never finished their software.
One prototype was made, but without
software, hardware is truly useless.

Q-What's your general procedure behind
bringing a new product to market - from
idea stage to finished product?

A-That depends on the kind of product.
Some go through multiple stages of
prototyping, others aren't even proto-
typed but go straight from idea into
the CAD system & into production. It
all depends on the amount of new
developments that go into a product. If
you take the X-Surf for example, there
was hardly any new development in it.
The Zorro interface was proven
technology from the Buddha IDE
controller, & except for the PnP
isolation of the Realtek Ethernet chip,
there was nothing new to develop. The
card went from idea into mass-
production within 10 days, where most
of the time was spent on finding
mechanical solutions for the metal
bracket & the boxes. Sometimes I still
hand-wire prototypes, but most of the
time, a prototype already looks very
much like the final product because it
takes about the same amount of time to
design a PCB as for me to hand-wire a
prototype. For most products, it's
necessary to make at least 2 or 3
initial prototypes, not only for me,
but also so a programmer & a betatester
have something to work with. It would
be a waste of time to do that all
manually, so prototype PCBs are mostly
the first step after a proof-of-concept
in the simulator of the programmable
logic chip design programs.

Q-How much of the work do you do
yourself?

A-When it comes to hardware
development, I do most of the work
myself, but when it comes to software,
I depend on others. I can do very basic
test routines ("hardcoding"), but any
OS-related programming is over my head.
My programming knowledge ends at 6502
assembler on the C64 & a little bit of
Turbo Pascal on the PC. Oh, & Basic on
the ZX81/C64!

Q-What is your best selling item, & how
many units have you sold this so far?

A-That's easy to say: The Catweasel
is the top seller. More than 5200
units have been sold in the past 10
years, where other well-selling
products of mine hardly come close to
3000 units. This is mainly caused by
all the different versions of the
floppy controller that I designed. I
have eleven different designs in my
CAD system, where ten were actually
mass-produced, including the latest
MK2 "anniversary edition". Other
products experience one, maybe two
revisions over their lifetime.The
Catweasel will be outnumbered by my
ADSL2+ system within one year. I have
requests from all over Europe & even
from Africa, & I'm in the lucky
position to choose the best offer for
the next contract.

Q-What exactly is a Flipper interface?

A-The Flipper interface is a bridge
between the Amiga & the mainstream
computing world. I invented it during a
time that seemed like the transition
between classic Amigas & the next
generation PPC Amiga machines. I always
wanted my hardware to keep it's value a
lot longer than ordinary expansions, &
the Flipper interface adds to that:
It's a dual interface for the same
piece of hardware. One side can be
plugged into a Zorro slot of an Amiga.
Autoconfiguration makes it available to
the Amiga OS. If the user switches to a
modern Amiga with PCI slots, they take
out the card, flips it around & plugs
it to the PCI slot of a PPC-Amiga or a
mainstream computer with PCI slots.The
Flipper interface has only been used
for the Catweasel MK3 so far, but it's
also planned for the Delfina card with
some extensions. However, I won't
promise a release date for the Delfina
Flipper interface, because I don't want
to disappoint anyone. I have promised
it for too long & didn't find the time
to actually do it. With the amount of
work I currently have, I have no idea
when I can find some spare time to
actually make the flipper interface for
the Delfina. For all those people who
want the Delfina in their Zorro based
Amiga, I have a special offer for a
combination of the A1200 clockport
Delfina card & a Zorro card with a
clockport.

Q-You also have another soundcard, the
Atlantis. What's the difference between
this one & the Delfina?

A-The main difference is that the
Delfina is available & in stock.
Atlantis was only made once, & the
prototype has been demonstrated on
multiple shows. However, the design
was never brought to a state where it
could be called "production-ready", so
I shelved it forever & did the
cooperation with Petsoff for the
Delfina instead. One of your most
famous pieces of hardware within the
Amiga community today is the Catweasel,
which is a floppy controller, simply
put. Maybe you could explain a little
more about what exactly it does?

Q-Is it possible to just plug in any
3.5" drive you can get your hands on, &
then use this to read all sorts of
weird floppy formats, such as an Amiga
formatted 1.76Mb HD disk?

A-You got it -- it's mainly a floppy
controller that takes standard PC
floppy drives & uses them to access
all kinds of floppy formats, including
Amiga DD & HD disks. The controller is
available for various Amiga models &
for PCs with Windows or Linux. For
5.25" disks, does it require any
specific sort of drive, or can you plug
any kind of pre-PC disk drive, or maybe
even a C1541 into it? The Catweasel
requires PC-standard floppy drives with
a 34pin Shugart connection. The C1541
drive only has the Commodore-IEC bus,
which is not compatible with the
Catweasel. If you want to read 1541
disks, just take a PC 5.25" drive &
insert the C64 disks, the Catweasel can
read the disks with that drive. Most
people still think that the drive
itself is incompatible, but really the
controller is responsible for the data
transfer. A drive mainly consists of
mechanics & signal conversion circuits
that do not care about the disk format.
The Catweasel therefore makes ordinary
disk drives truely multitalented.

Q-Does it handle any other formats
apart from the above mentioned floppy
sizes, such as cartridges/cassettes?

A-Neither cartridges nor cassettes use
standard interfaces such as the shugart
interface. However, if you have a tape
streamer that was used with old floppy
controllers, it would be possible to
design drivers for the Catweasel.
Especially the MK4 offers new features
that support such hardware, but I never
intended to support all the different
non-standard streamers, because even if
you're connecting them to the same
interface as the floppy drives, they do
need totally different commands that
are completely different from vendor to
vendor. The new controller features
mainly aim at disk formats that were
popular in the early 80's & 70's. There
are 8 & 3-inch drives that need a few
more hardware features, & the Catweasel
MK4 supports them with the forthcoming
floppy- adapter "Kylwalda II".

Q-For the latest revision of the
Catweasel, you added a SID chip, the
sound chip used in the C-64. How come?
I don't really see the logical
connection there.

A-The logical connection is made
through emulators. An emulator can do
almost everything that the original
machine can, with the limitations that
the hardware of the host computer
gives. One limitation is the floppy
controller, it can only handle MFM
format, so the C64's GCR-formatted
disks appear unformatted to the PC
floppy controller. The same applies to
the SID chip of the C64: If emulated,
you always have a delay between picture
& sound. Further, every SID has it's
own character because it's partly an
analog chip. You cannot emulate these
different sounds 100%, as every filter
characteristics of every chip is
individually different. A real SID
chip brings emulation a lot closer to
the original, but still keeps your desk
tidy. No need for multiple machines,
monitors & keyboards on one table.

Q-What platforms is the Catweasel
targeted at, & what's the story with
drivers for OS 4 & MorphOS?

A-The Catweasel MK4 mainly goes into
x86-based machines that are running
Linux or Windows. I have seen a
significant peak in sales when I
published the new Windows beta drivers,
which adds to these statistics. OS 4 &
the UBoot rom of the Amiga One also
support the MK4, with still a lot of
work to be done. I gave the source
codes of the classic Amiga drivers to a
programmer who is now working on a PPC-
native port of the multidisk device.
This will bring all the capabilities of
the classic Catweasel drivers to OS 4.
Since I'm not spending any money on
these drivers, I cannot give any
release date. The story behind MorphOS
drivers is easily told: I made
Catweasel drivers for MorphOS in early
2003, which created sales of about 30
units. I had to sell my Pegasos due to
a decision of the management of Genesi:
Dropping the price of the Pegasos by a
few hundred EUR meant dropping the
used-value of any Pegasos in the field.
To limit the losses that the MorphOS
port of the drivers had already
generated, I sold the Pegasos. About a
year later, a new MorphOS version came
out that was incompatible with the
multidisk.device, & people wanted a
free update from me. I refused, because
I don't have a machine any more, &
because I am not willing to spend money
on the development of drivers for an
operating system that currently does
not have hardware to run on legally.
What applied to the MK3 drivers in
2004 also applies to MK4 drivers
today: I will not spend any money on
the development of drivers when
there's no substantial sales to
expect.

Q-You wouldn't consider sharing the
driver sources with a MorphOS
developer, as you did for OS 4?

A-I wonder what's the difference of
me handing the drivers to someone, or
someone taking a good look at the
open-source Linux drivers. If there's
someone who seriously wants to work on
MK4 drivers for whatever OS, he should
approach me & ask. Instead, too much
time is spent in online forums, ranting
about others, but not really doing
something. Like I said before, a
conflict requires two sides to be
maintained. The "upper management" has
only used the deveopers of the
community to build business plans,
convince investors to spend money but
was only pushed around in the end (and
this applies to both camps). It's time
to build new alliances & set the
conflict between the communities
aside, especially because it was not
created by the community, but by the
management.

Q-Out of all your hardware
achievements, which 3 of your designs
are you most proud of, & why?

A-The Catweasel is surely among the 3,
as that's a product that turned into a
true self-runner. Hobbyists are using
it, & so are forensic laboratories,
including the US computer forensic
department of defense. The Catweasel
keeps surprising me, even after 10
years. We're constantly finding new
fields where it serves well, & with a
new programmer on the Windows drivers,
I'm expecting interesting updates,
especially in the field of data
recovery. The other 2 I'd like to
mention are fairly simple things, but
they were real challenges during
development: The Retro Replay for the
C64 does about the same as the Action
Replay did back in the day. However,
the logic chip that I used on the
cartridge is full of timing-tricks &
manual on-chip routing to make the
design fit & to make it work with
all C64 models. I solved many problems
that arose from mixing high-speed CMOS
logic chips with the slow speed logic
chips of the C64 without customers
even noticing. The same applies to the
Buddha IDE controller for the Amiga,
so these two are on the same level of
complexity.The last thing I'm really
proud of is Keyrah. The user can take
an old keyboard of a C= computer, & use
it on the USB port of a mainstream
computer (PC, Mac, Amiga anything else
that has USB -- even X-Box!). On the
outside it looks like a simple micro-
controller scanning the matrix &
passing the information to the host
system. However, if you're a bit into
electronics, you might notice that
there are very few components on
Keyrah. One thing that most people I
spoke to thought was impossible to
eliminate was the crystal. I found a
way to time the USB communication
according to the tight specifications
of the USBIF (I became a USB-IF member
in 2005).

Continues in part 3