Bits from Bill

Technology thoughts leaking from the brain of "Bill Pytlovany"

Sunday, December 09, 2007

Commodore 64: 25th Anniversary Celebration

The Computer History Museum in Mountain View, CA is having a special celebration on Monday, December 10th. Invited speakers include former CBM president Jack Tremial, Apple pioneer Steve Wozniack, Amiga developer Adam Chowaniec and William C Lowe, father of the IBM PC. I’m sure my invitation was lost in the mail.

The Commodore C64

Let me just say that the C64 changed my life like no other device. It was like a drug that addicted me with its charm and personality. It helped me find new love, friendship, travel and a completely fun new career. Call me sentimental but it allowed me to find confidence and purpose in my life.

I had become quite the advocate of the C64/128 when I met up with a guy named Steve Case and his friend Marc Seriff. We shared a vision that personal telecommunications could be so much easier. I won’t bore you with sorted details of my C64 history but I’ll share some of my favorite tricks and memories that might be interesting to other C64 users.

Q-link animation
Click for Video of my 1985 Q-Link Demo

I used to bring my Commodore Vic-20 with me into my chemistry lab in college. Instead of spending one hour studying the lab work the night before, I would spend three hours writing a program to input and process my lab results. I thought my professor would be impressed but he was more excited that I could make the computer duplicate the sound of a phone ringing.

Unlike other computers of the time, the Commodore 1541 floppy disk drive had a processor and memory which allowed it to be programmed as well. While this was typically used for copy protection, someone actually wrote a program that made the disk drive play the tune “Bicycle Built for Two” by moving the drive head back and forth at different frequencies. It was a cute trick but not one I demo’d very often.

My favorite trick was created by programmer, Michael J Henry. It was easy to customize the text in programs by editing characters on the floppy disk so you could make the screen say anything. Well, Michael’s trick discouraged people from removing his name on the screen. The “L” in his first name was represented as “4C” which in the machine language of the C64 was also the code for the instruction JMP or Jump to the address of the next two bytes. At startup, his program would jump to the physical screen address where the “L” was visible and it would cause the program execution to jump to the address “204A” which was represented by the “space J” in his name. If anyone changed his name, the program stopped working. If you were able to follow that you can claim geek status.

One person missing from Mondays’ event will be my old friend and mentor Jim Butterfield. In doing research for today’s post I discovered that Jim passed away peacefully June 29th of this year.

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Anonymous Anonymous said...

I had C64.
I have very good associations:)))

6:22 PM  

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