Thu, 13 Jan 2005

First Computer

My friend the orangeguru posted this little tale of his first computer yesterday. So, since I'm another year older today, I figured it would be interesting to do the same. The year was 1979 ... at the left is a photo of a device very similar to the first computing device I owned: the COSMAC Elf. Mine looked slightly different, as I had mounted it in the case of an old Radio Shack CB base unit.

  • Processor: RCA 1802 (8 Bit CMOS), 1 MHz
  • RAM: 256 bytes
  • ROM: none
  • Display: two seven segment LED's

I also had a speaker wired across the Q line of the processor to produce some simple audio output. I could've expanded the RAM to a whopping 1 KB, but that would've cost me an extra $100, and besides, what would I ever do with all that free memory?

Programming was a simple matter of setting the eight switches on the front panel to the desired machine instruction (in binary) and them pressing the 'Load' button. My major software accomplishment: programming the little thing to play the song Down in the Valley (the link is to a MIDI version that sounds a whole lot better than my monotone creation). If I recall correctly, it took several hours to figure out exactly how to manipulate the line to get the right tones, and then program the machine. The program ran for about 30 seconds...

Amazingly, there is still a community of COSMAC Elf users/builders on the 'Net. In fact, the "blueprint" (from Popular Electronics, August 1976) I used to construct my little electronic marvel is actually up on the 'Net here.

OK, now I feel really old.

/Home | 2 writebacks | permanent link

On
orangeguru wrote

On
Dave H. wrote

Another Test

comment...

 
Notes: If you put a <mailto:> link in the URL field your address will not be mangled: this could be a bad idea as your email address could be easily harvested by bots designed for SPAM. The comments field should now format correctly for line feeds and carriage returns: when you hit the 'Enter' or 'Return' keys in your comment it should break to a new line. The text should wrap cleanly. Please let me know if it doesn't. No HTML tags will pass through - entering links seems to be the main cause of comment SPAM. Also, please be sure that Javascript is enabled in your browser before attempting to post a writeback. Sorry for any inconvenience, but this really helps cut down on the amount of comment SPAM I have to deal with.
 
 Name:
 URL:(optional)
 Title: (optional)
 Comments:  
Save my Name and URL/Email for next time