Q: Could you tell us when you first began learning machine language? Was it on the Commodore PET?
It was on the Commodore PET in 1981 and I only had a tape player for storage at the time.
Q: How did you learn machine language? BTW I still use your sector editor to this day for editing C64 disk files.
I bought a couple of books on the 6502 and just started writing programs in hex using the machine language monitor. After a while I started disassembling machine code programs that I came across like Space Invaders.
Q: You were the author of some high-quality games including Paladin (Defender clone), Land Slide, Bugg (Centipede clone), and Candy Man (a large screen Pac Man game). Were these all written in a hex editor?
Yes, those were all written in hex.
Q: If so, how did you design the components of the games? For example in an assembler one could insert and edit existing code whereas in a monitor you'd have to relocate code or jump to new code if you forgot to include something.
I would leave small gaps between the subroutines in case I had to modify the functions or fix bugs. If I didn't leave enough room I would relocate the function to a new address.
More of a comment than a question. What amazed me about Paladin was the ability to animate multiple segments at once. For example, you incorporated the radar screen, and at the same time could have the volcano erupting while an explosion effect took place when you destroyed an enemy. From a programming perspective this is fascinating in that each routine didn't disrupt the other. The explosion didn't overwrite the screen.
Do you remember any details into what went into designing Paladin, was it written on paper first? Did you play Defender a lot in order to visualize the playability?
I had a friend who played Defender a lot and he was the one that helped me design the game as I was not intimately familiar with it.
Q: There are two versions of Paladin, v1 and v2 yet both appear to be similar. Can you recall what the differences are?
I think v2 was just to relocate some memory variables as they conflicted with system RAM memory (on newer PETs) and caused the computer to crash when you exited the game. The C64 version of Paladin was written in assembler by un-assembling the PET version and then making changes for color and updated sounds etc.
Q: Was your software available for free on the PET or was it commercially released?
Free
Q: Aside from what's already been released, were there any titles that never saw the light of day or have been lost in time (Commodore PET and 64)?
No
Q: You've had a long career in the computer gaming industry including designing some innovative copy protection routines. I can remember trying to copy Beach Head II with a nibbler and failing. Do you still create protection schemes? Are you in touch with Brian or Kris of Piratebusters days?
I have not talked to Brian in about 20 years, I've been in touch with Kris on and off over the years. I haven't done any copy protection since my C64 days.