Re: A contest...with a prize!
- Posted by mountains at MINDSPRING.COM Jun 03, 1998
- 791 views
At 12:04 AM 6/3/98 -0400, Jacques Deschenes wrote: >This is code for RCA CDP1802 microprocessor. The computer was probably a COSMAC ELF >Popularized by "Popular electronics" in 1977 (or 1978). >I don't understand yet what is does. (what device was connected to output 4, line Q >and input line EF4 ? ) >On my machine there was a LED on the Q line so codes 7B and 7A was flashing de LED. >I connected a speaker on that line too and produce sound effects with it. >I even code a program to play tunes. >--- Hoo! I didn't expect a reply so quickly. You are correct (enough to win the prize - where shall I send the coupons?) I wondered if there was a "signature" in the machine code that would be recognizable, and sure enough, there was - strange how some things stick in your memory, even for 20 years. This ran on an ELFII, which had a 2 hex displays connected to output port 4 (64), a hex keypad, and an Input key connected to input 4. There was also a relay driven off the Q line, which supplied 110v ac to a device. If you're interested in a perfect, working 1802 computer in hirez graphics: Quote: "Compatible with Windows 3.1, 95, and NT, as well as WABI (Sun), WINE (X-windows), SoftWindows (Mac), and other Windows emulators. (And if you don't think it's ironic to run a simulation of a 14-year-old microprocessor under an emulator of an 8 year old operating system running on an expensive new personal computer, then your sense of irony is obviously in need of a checkup! " >--- >--- Regards, Irv