Contents | < Browse | Browse >

      Interview With Pieter van Leuven, Author of the Vic-20 Emulator
  George Lui           

[George Lui is a big fan of the Vic 20 emulator for the Amiga.  He decided
to interview the author via e-mail.  Here's what he got. -Jason]

> 1)      Did you have a VIC 20 and why ?

Yes, I still have it.  This was the first computer that I owned (and used).
I was interrested in computers and I had the choise between buying a ZX-80
or a vic-20.

> 2)      What did you do with it ?

Write very simple programs on it.  I learned programming in machine
language on it.  And ofcourse playing games on it.

> 3)      What led to the creation of your VIC 20 emulator ?

I wanted to do something with my amiga.  So making an emulator was a nice
project.  I choose the VIC-20 because that was the computer I owned for I
bought an Amiga.  I knew allmost all the details of the VIC's hardware.

> 4)      How long did it take ?

1/2 Year (with a lof help from friends)

> 5)      What programs/hardware did you use ?

DevPac asembler and debugger, SAS C-compiler, an Amiga 2000 and a terminal
to display debugging information.

> 6)      What were the difficult parts in writing it ?

The 6502 emulator.  When VIC program didn't worked it is often a wrong
implemented 6502 instruction.  To find out whihc instruction causes the
problems can take some time.  Especialy when the faults are not in the
emulator but in the vic-program.  I was looking for a fault for months and
the problem was that I initiated all the addresses with the value 0.  In
the real vic it has random values.  Cosmic Cruncher forgot to initialise on
variable.  When it was not equal to zero the program worked (most of the
time on a real vic).  On the emulator it was always going wrong.

> 7)      Did the graphics and sound emulation proved to be trickey ? 

It's implemented trickey.  But is was very easy to findout how it worked. 

> 8)      What are the main steps in writing an emulator ?

Find out a smart way how to emulate the hardware.  The processor is not
that difficult. 

> 9)      Do you think that BASIC should be popular again ?

Nope, there are much better languages.  I prefere C because it's gives you
the possibility do some dirty programing.  But one of the better program
languages is modula or other kind of languages that looks like modula.

> 10)     Did you have fun writing it ? 

Yes, it kept me from the street :-)

> 11)     Are there any plans for a future update on the emulator ? 

When I buy a new kind of computer.

> 12)     Will you port the program to other platform ? 

See above question. (Probably on a PPC-platform)

> 13)     80's micro emulation seems to be popular these days. Why do you think 
>         that this is so ?

Just sentiment.  A lot of people started with computers from the 80's.  Now
you need a lot of computer power for programs but some of the old games
where more enjoyable then the games from now.

> 14)     What are your thoughts on the present state of the Amiga ?

Not that many improvements the last years, but still a lot better then the

> 15)     What do you think of Amiga Technology ?

I hope they can continue the Amiga-line with a lot of new

> 16)     What do you think of 'The Amiga Report' ?

Sorry, I don't know 'The Amiga Report'

> 17)     What do you think of Jason Compton ? 


[Oh well. -Jason]

> 18)     What would be your dream Amiga machine ?

A multi processor system with a flexable Operating System.  And ofcourse
nice graphics and sounds for games.