Commodore Free 13/Commodore_Free_Issue_13_2007_Commodore_Computer_Club.d64/t.iv jan

Text File | 2023-02-26 | 14KB | 466 lines

uInterview with Jan Derogee creator of
1541-III http://jderogee.tripod.com/
project1541.htm

Q Please introduce yourself

I'm Jan Derogee. I'm an electronics
engineer. The C64 was my first computer
& a while ago I needed a project that I
could fill my time & the hole in my
second-hand C64SX with, the 1541-III
was just that project.

Q How were you introduced to computing?
As a kid I just wanted a machine that I
could tinker with & build things for,
but the first years were only simple
BASIC programs & games... lot's. The
C64 was switched on everyday & it
thought me a lot.

Q When did you first come across the C=
Brand?

My sisters boyfriend had a C64 computer
& was an easy source for software... so
I wanted a C64

Q Please tell us about the 'project
1541-III' what does it do for the user

The 1541-III is the missing link
between .D64 files & a 25 year old
computer without the hassle of cables
of difficult PC-tools & because it is a
hobby project it can always be better,
many years of tinkering ahead... the
perfect project for me & because others
like it so much it encourages me to
keep making it better.

Q Was there a version 1 & 2? or is this
reference to the 1541 version 1 then a
redesigned version 2?

The 1541-III is named 1541-III simply
because there was a 1541 & 1541-II
Since I wanted my project to be the
next logical step in IEC drives I named
it the 1541-III a name that people
could easily remember, a small bonus I
did not think of when I started the
project, simply I never expected that
anybody else wanted it.

Q Can you talk us through the design
process?

When I started this project I didnt
knew anything about the IEC-bus, but
how difficult could that be? What a
mistake that was. Although I am pleased
with the IEC-bus concept, it is a very
difficult concept when you start
digging, the details are difficult to
figure out.

Because it is a bus, it is difficult to
see what device/computer is doing what,
so monitoring the IEC-bus with a logic
analyser is not really useful, but
since good documentation is difficult
to find..

Monitoring the bus is the only option.
But since I did not have a logic
analyser, I decided to write some
software for my PC's parallel port &
that should do the trick. It has helped
me out a lot, but still a lot of
questions are not answered, I'm still
learning. After knowing how the bus
works, you still have to handle the
medium itself... MMC & SD-cards, it was
HELL. The documentation of this is very
clear & although not all info is
available for free there is info to be
found. But when you start coding
software that uses a card MMC or SD you
start to discover that every
manufacturer uses his own variation of
the MMC standard & you start wondering
why the standard was invented. Scandisk
was the worst. But after a while coding
for all exceptions you discover that it
only works if you test all situations
for all sorts of cards...

So I've bought a lot & borrowed some
from work & some users where very
friendly in sharing there results... &
finally it resulted in a stable
situation where most of the cards are
excepted (again I'm learning the hard
way).

Well then there is the DOS, simply
because the DOS commands are required
for using the device. I decided I'd
take a shortcut & implement only the
LOAD & SAVE commands, this makes it a
lot easier since you do not have to
handle all the independent DOS commands
as long as you mimic the behaviour of a
real drive a small detail that is now
causing trouble, simply because my
little shortcut prevents me from using
the 1541-III with a Prophet cartridge,
because the P64 uses low level DOS
commands instead of LOAD (regarding
directory reading)

This behaviour is nothing special but
it does requires a complete rewrite of
all my OPEN-CLOSE-etc command handling
inside the 1541-III. Oh & of course I
wanted to use a nice display I first
uses a 2 line character LCD, these are
easy to obtain but they cannot handle a
lot of characters

So I decided to use a cheap Nokia
display that is very small, cheap &
holds a lot off info & is completely
graphic, the result is very nice & I
decided to not support the LCD anymore

Then .D64 decoding, D64 files are an
exact copy of the 5 1/4 disk format, so
when you open up any disk drive book,
you know how to decode a D64. But still
there are a few details that are not
described in any book but do need to be
handled correctly

So every little detail & step is solved
& learned about with the end result a
1541-III. Regarding the FAT driver, I
was fortunate, I could copy it from
another application (saving me a lot of
work)

Q How can we obtain a device, do you
sell them?

First I started the project as a DIY
project, but to help-out those who are
not skilled technicians I decided to
sell some complete assembled units. And
suddenly nobody can handle a soldering
iron any more. So my first batch was
sold within no time at all. Although it
took me quite a while to solder all
those little PCB's test them, drill,
file & glue taking up all my spare
time

Then a lot of people registered for the
second batch which now more then a year
later is finally being handled within
the end of 2007 (if nothing comes
between). This is the last batch
because some components are hard to get
& I'm not a company I have a life also,
this project is taking up all of my
spare time & that's not good socially

Q I notice you used recycled Nokia
phone displays was this an
environmental decision?

Nope, purely practical. Since using a
display that is produced in such large
quantities. It should be easily obtain-
able & cheap. An ordinary character LCD
holds less characters, uses more
current, is bigger, requires more
wiring & is cannot display graphics.
The Nokia LCD beats the char LCD on all
fronts. And of course because the Nokia
display is very small it can be glued
in the case very nicely without
noticing that it is an recycled old
phone display

In short, the Nokia display is perfect
for this project. Of course environment
was indeed a very important part in my
decision

Q You mentioned your design is 'open
source' so others can make mods & sell
completed units

Correct, I designed this project for
myself & I consider it as a great
compliment that others are liking the
project & want to use it. So if they
want to build it & sell it... go ahead.
But please mention my name & keep it
compatible if you add some changes. By
building more units that use the same
firmware, bugs are detected quicker &
solving them should be easier

I consider it an positive point that
more people are using it & having fun
with it. Example is pyrofer, these guys
made a perfect DTV version of the
1541-III hardware. It is compatible
with the 1541-III itself & therefore it
uses the same software. It helped me in
finding a lot of 'bugs' & by reading
the forum I've learned about a lot of
detail I never would have thought of

Q Would you be upset if a commercial
company started manufacture of the
devices?

Only if the did not ask me first...
There are a lot of users wanting the
1541-III & I could never build a unit
for all of them, so I don't see what's
wrong in a company building 1541-III's.
My goal is building a useful device for
the C=

Q How do you feel with other 'clone'
projects Using your design guides, I
guess it makes you feel good because
after all you gave the design away

Correct... it motivates me greatly. And
it keeps me going regarding improving
the firmware

Q Why did you give the design away what
prompted the decision

The C64 was my first computer & a lot
of good memories I have to thank this
machine. During my first presentation
on the HCC Commodore Gebruikers Groep
show in Maarssen, I found out that I
was not the only one who wanted such a
device, so the most logical things was
publishing the whole design on the
internet, for all who want to build it,
go ahead & please... have fun with it.

Q What is open source?

In my opinion open-source is making
source code available, so all can see
how it works & learn or improve it,
helps fixing bugs or alter it to suit
your personal needs. By giving it away
I expect that people who use it & alter
it will notify me. At least this is
what I do when I find something on the
net & want to use it

Q Did the device need amending to work
on other C= machines for example C16 or
+4

The VIC has a smaller screen than a
C64, so I tinkered some with the
directory routines in order to make it
display more nicely. Other then that it
required no special coding. But mainly
there are not many VIC/C16/+4 users
with the 1541-III or at least they are
not reporting bugs

There is a small problem with the C128
in 128 mode, for some reason there are
some problems during start-up. But I
think it has something to do with my
'shortcuts' described earlier

Q Did you find 'design features'
(rather than calling them bugs) of the
IEC protocol

To be honest, there is not much
documentation on the IEC bus, but a
document written by Jim Butterfield
(which was considered to be the most
sacred document of all, due to his
clear writing)

The things not described in that doc
could not be found elsewhere so the
things I found out were all unknown & I
guess there are some 'design features'
between them, but since I did not know
they should not exist I don't care in
finding them the hard way.

Q Are there more of these device
Designs to come from yourself or are
you happy with the hardware as it is

The 1541-III stays unchanged in order
to maintain 100% compatibility with the
current firmware. Maybe in the future
there will be some spin-offs using the
IEC routines, but I can't think of a
short term application

Q I notice on the website that a kit is
available for purchase but you are so
busy that user will have to wait a long
time to receive kits due to you having
little time, so your design is more a
reference than a purchase item?

Correct, & my spare time was also the
main reason in publishing this project
in such a way that people can build one
themselves. So indeed it is not really
a purchase item

Q So the project is really a labor of
love & a design guide rather than a
product to purchase off-shelf

Correct indeed. But I want to make sure
that everyone understands that this is
a very nice DIY project (for a skilled
technician)

Q Have you thought about approaching
someone else to mass produce the design?

Yes, but I know it will never make me
rich & I do not intend to make myself
slave of my own hobby project

Q With the age of C= hardware I guess
there will be a time when all units
will fail, from a Personal perspective
I wanted to hand my C= machines to my
young son so he can experience the
thrill of computing, do you think one
day C= machines will fail & be beyond
reasonable repair

Yep, this is a fear that I keep in mind
constantly, fortunately there are a lot
of people coding FPGA versions of the
C64, VIC20, etc. (the AMIGA by Dennis
van Weeren is a great example)

This keeps the hardware alive in some
sort of way. But personally I think
that the retro computing is something
that will last for another 25 years
tops

Most people who are retro computing now
are people, who started with such a
computer when they were young

These people will get older with the
same age as their machines & by the
time the last C64 dies retro computing
will not be as big as it is now & the
hardware itself will not be required
any more as there are plenty of
alternatives/emulators on PC's or FPGA
versions

But honestly, I love the attention
retro computing has now. And when I
attend to a C= meeting & I start my
good old C64 & I connect my drive... I
feel young again (considering I'm 33),
when life was only fun & almost without
problems (the only problems were
finding enough empty disks)

So to be honest, I hope retro computing
stays for at least another 50 years!
And when my C64 dies, I guess I have to
redesign the part that is broken using
modern components

I hope my answers are not too long &
that they are suitable for publishing.
Good luck with your article.
Regards, Jan

PS: regarding my personal status:
I was born in 1974. I'm married & have
3 kids; a son 4.5, a daughter 3.5, & a
son 1.5

You can imagine that they require a lot
of time & that they do not always
understand their daddy's passion for
'old computers'. They are my main
'project' & motivation in life

They can amaze me with the simplest
things, frighten me with a single move,
put my patience to the test without
knowing it, ask questions I never
thought off, drain my energy & make me
fall asleep before my head hits my
pillow, then wake me before my alarm-
clock does. But most off all they give
me strength, a simple smile or thanks,
the kiss goodnight, the hug before
daddy leaves to go to work or reading
from the bed-time-story-book before
they go to sleep. Those are the things
that make me happy.

Related projects: 1541-III DTV

The 1541-III stripped down to a version
perfectly suited for use INSIDE a
C64-DTV. A great idea made into a real
product by Pyrofer. This is a project
that uses the 1541-III source-code on a
slightly different PCB in order to suit
the C64DTV. For info, updates & support
about this project refer to Pyrofers
Site:http://www.pyrofersprojects.com/
 15413.php

Pyrofer also has a very useful forum
worth visiting, even if you dont have
a DTV: http://www.pyrofersprojects.com/
 forum/index.php?sid=e0ce333e3c
 4e6494995b5c2d30868bc1

MMC2IEC
Lars Pontoppidan made an AVR version
the 1541-III DTV. This version is has
very few components & is easy to
rebuild. His projects development was
stimulated by the 1541-III project & is
rewritten especially for the AVR
microcontroller. Read all about it at
his website & be amazed by this tiny
PCB that will easily fit into your
C64DTV. For info, updates & support
about this project refer to Lars
 website: http://pontoppidan.info/
  lars/index.php?proj=mmc2iec