MOS-6501 / MOS-6502 History - Page 1
Forum section: electronics / general

author: mon2
author_rank: Frequent Contributor
timestamp: July 11, 2022, 02:46:52 pm
content: What a GREAT CPU in its time !!Thanks Rodnay Zaks for an amazing book on programming this CPU - loved reading every page of it in high school.Loved the Atari - to Sam Tramiel, should have accepted your job offer back in the day. I may not be working today if I hadOh the memories...

author: coppice
author_rank: Super Contributor
timestamp: July 11, 2022, 03:02:00 pm
content: Stripping down the CPU actually made little difference to the fundamental cost of most systems. When you added in all the memory, peripheral, clock and other hardware needed to make a complete system there was little you could do by just stripping down the CPU. The 6502 wasn't inherently that much cheaper. It was just priced in a very aggressive way to kick start the market.

author: brucehoult
author_rank: Super Contributor
timestamp: July 12, 2022, 01:26:44 am
content: Quote from: coppice on July 11, 2022, 03:02:00 pmIt's pretty hard to make a profit on a $99 Commodore 16 or zx80 if the 6502 or z80 costs $250.

author: Bud
author_rank: Super Contributor
timestamp: July 12, 2022, 04:30:16 am
content: There are better adult style videos from Computer History Museum channel.

author: coppice
author_rank: Super Contributor
timestamp: July 13, 2022, 12:24:03 pm
content: Quote from: brucehoult on July 12, 2022, 01:26:44 amAnd its hard to make a profit on a $99 Commodore machine when all the non-6502 parts cost hundreds of dollars. That's why the first Commodore PET cost about $800 dollars before you started adding enough peripherals to make it useful.

author: brucehoult
author_rank: Super Contributor
timestamp: July 13, 2022, 12:50:27 pm
content: Quote from: coppice on July 13, 2022, 12:24:03 pmDidn't take long to get cheaper:1977: Commodore Pet, Apple ][, TRS-80 $600-$1300 base price1980: ZX80 $99.Of course the ZX80 was crap, but still, you could learn Z80 machine code programming on it (I did).By 1982 the Apple ][ got cheap enough that my father (42 years old at the time, and a farmer), who knew nothing about computers, bought one with 64 KB RAM, dual floppy drives, and a C-Itoh printer.

author: coppice
author_rank: Super Contributor
timestamp: July 13, 2022, 01:05:17 pm
content: Quote from: brucehoult on July 13, 2022, 12:50:27 pmExactly. Whether the design was based on a 6800, an 8085, a Z80 or a 6502, the prices all came crashing down when the time was right. The simplification of the 6502 over the 6800 was irrelevant.

author: Kleinstein
author_rank: Super Contributor
timestamp: July 13, 2022, 03:13:53 pm
content: For the ready made computers like PET and TRS80 the price difference was not that relevant, though the 6800 and 8085 were still quite a bit more expensive initially. However for the simple single board computer kits that price difference was somewhat more relevant.I remember that the 8085 kept beeing rather expensive, despite of the Z80 as a good alternative.Comodore did not really care about the price of the 6502 for there computers, as for a long time they owned MOS.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 13, 2022, 06:39:58 pm
content: Those that seem not to think that the difference between $25 and $250 for a CPU would be significant back then (yeah, whatever), if they exclude the home computers (which would be hard to ignore in the 80s) for which $250 would be a very, very big chunk of the total cost, they still need to consider that many big manufacturers at this time just did NOT believe in a market for personal computers whatsoever. IBM was very hard to convince at the time. The IBM PC was pursued almost out of sheer luck back then, against a lot of internal resistance. Also see what Commodore was saying, they just wanted to make calculators. And the list goes on.So it would take really, really cheap components to manage to even create a *market* for personal computing. And the rest is history. Once the cheap CPUs were out, everybody, even the big ones, followed and prices plummeted.

author: coppice
author_rank: Super Contributor
timestamp: July 14, 2022, 02:09:59 am
content: Quote from: SiliconWizard on July 13, 2022, 06:39:58 pmHas anyone said that a $250 CPU was not a problem for mass adoption?