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Hackaday wrote:

The 6502 is the classic CPU. This chip is found in the original Apple, Apple II, PET, Commodore 64, BBC Micro, Atari 2600, and 800, the original Nintendo Entertainment System, Tamagotchis, and Bender Bending Rodriguez. This was the chip that started the microcomputer revolution, and holds a special place in the heart of every nerd and technophile. The 6502 is also possibly the most studied processor, with die shots of polysilicon and metal found in VLSI textbooks and numerous simulators available online.

The only thing we haven’t seen, until now, is a version of the 6502 built out of discrete transistors.

Source Link: http://hackaday.com/2016/05/16/a-dis-integrated-6502/

Why do I think we've finally pinned down in meatspace the poster known as bhtooefr?

biffzinker wrote:

Hackaday wrote:

This was the chip that started the microcomputer revolution,

Not strictly correct. The Altair 8800 preceded the Apple I by about a year, and used the Intel 8080 CPU. Microsoft also got their start on the Altair (the Altair BASIC interpreter was their first product). So while the 6502 arguably gets credit for popularizing PCs and taking them mainstream, the 8080 was really the chip that started it all.

I remember alot of things using the Z80 as well (my Sega Master System, TI calculators, lots of misc others).

The Egg wrote:

I remember alot of things using the Z80 as well (my Sega Master System, TI calculators, lots of misc others).

8080 was still first, and I believe the 6502 pre-dates the Z-80.

Z-80 ISA was actually a superset of the 8080, and (initially at least) clocked higher than the available 8080 parts. So a lot of enthusiasts of the day (myself included) upgraded their S-100 systems from a 2 MHz 8080 to a 4 Mhz Z-80 at some point. Unfortunately, most of the RAM of that time was only rated for 2MHz (synchronous FSB so everything had to run at the CPU clock speed), which necessitated the use of "wait states" (basically stretching every memory cycle by 1 clock cycle to give the RAM an extra 250ns to catch up). Some things never change... it's analogous to today where we need to relax our RAM timings to overclock the RAM... except the clock speeds are multiple orders of magnitude faster!

just brew it! wrote:

to give the RAM an extra 250ns to catch up)
multiple orders of magnitude faster!

The funny thing here is of course that DRAM random access latency is one order of magnitude shorter than in 1983 (that's the year when I got my Sinclair ZX Spectrum).

Wirko wrote:

just brew it! wrote:

to give the RAM an extra 250ns to catch up)
multiple orders of magnitude faster!

The funny thing here is of course that DRAM random access latency is one order of magnitude shorter than in 1983 (that's the year when I got my Sinclair ZX Spectrum).

Yup, the big difference is in the streaming bandwidth once things get going. The speed of the underlying DRAM cells has barely budged in nearly 2 decades; successive generations of DDR have increased the net bandwidth by adding banks to each DRAM chip and doing the equivalent of RAID-0 across them.

(1970s SRAM tech, as used in S-100 systems, had no concept of bursting; each byte was accessed individually.)