schriste@uceng.UC.EDU (Steven V. Christensen) (12/31/89)
For some reason, I have this great urge to build something micro-processorish (I am an electrical engineer in school). I have seen a couple of projects in some electronic magazines using the RCA 1802 microprocessor. Can someone tell me how much one of these costs? And where to get an 1802? Anyone had any experience with it, or done some interesting computer projects in general? Thanks for your opinions! Steven -- Steven V. Christensen U.C. College of Eng. schriste@uceng.uc.edu
wiz@xroads.UUCP (Mike Carter) (01/10/90)
In article <3218@uceng.UC.EDU> schriste@uceng.UC.EDU (Steven V. Christensen) writes: >For some reason, I have this great urge to build something micro-processorish >(I am an electrical engineer in school). I have seen a couple of projects in >some electronic magazines using the RCA 1802 microprocessor. Can someone tell >me how much one of these costs? And where to get an 1802? Anyone had any >experience with it, or done some interesting computer projects in general? > >Thanks for your opinions! > > Steven > >-- >Steven V. Christensen >U.C. College of Eng. >schriste@uceng.uc.edu STeve: Here at Sky Harbor we have some automated parking equipment that uses the RCA 1802. It's a fairly rugged little processor..seems to stand up to the daily punishment pretty well and during the lightning storms I only have trouble with the 6821's . The 1802 can be picked up from Hamilton Avnet..although after playing with this CPU fro several years, I can't seem to figure why anyone would want to monkey with one on a new project. It's absolutely retarded when you compare it against what is available. Price wise, I think we're paying about $20.00 a piece for these relics.. but I'd have to go back to the office to make sure...they wont sel them to you unless you have an order of at least 50...this would prevent a casual hobbyist from doing a purchase....unless you can scrap around and dig one up out of some old dinosaur resting in the cobwebs at a local used parts dealer. Well, I guess I *could* send one off to you if you insisted. --that's if you're a glutton for 7-line I/O -Mike
wtm@neoucom.UUCP (Bill Mayhew) (01/16/90)
I agree. The 1802 is a rather brain-dead microprocessor. There are some very odd machinations that the programmer must put up with for calling and returning from subroutines on this beast. Of historical note is that the RCA Cosmac 1802 was virtually the first, if not *the* first CMOS process mircoprocessor. This made the 1802 a very attractive candidate for space-borne electronic control systems, military electronics, and harsh enviornments with high electromagnetic interference levels. I worked for a certain government agency in 1979 - 1980, and the 1802 was the only microprocessor that we could use because the 1802 was the only MPU chip that was fully qualified for space avionics. Yuck! We were looking forward to seeing CMOS versions of the Z-80 and 8080 that were then on drawing boards. Thre are a lot better chips around to use for learning projects. Ironically, the 1802 is rather expensive if you can find any stock, becuase the 1802 never became terribly popular. Once CMOS versions of popular consumer chips became available, the 1802 with its quirky instruction set became less attractive. The Z-80 and the ubiquitous 6502 are available for just a couple of dollars and are quite easy to assemble into simple systems. There are a lot of books tageted at the two aforementioned chips. The 65C02 is nice to work with because the desing is fully static and does not have any maximum durations on clock states. Steve Ciarcia has several build-it-yourself type books. Joseph Carr also worte, "Interface Your Microcomputer to Virtually Anthing", which is a good starter text. Bill wtm@neoucom.edu (...!lll-winken!scooter!neouocm!wtm)