The 6502 CPU Powered a Whole Generation!

Support The 8-Bit Guy on Patreon:

Visit my website:

[fuzzy]

I like how the thumbnail is him offering the cpu like it's a quest item

[TechDeals]

A few thoughts...
1. I feel this only scratches the surface. I get that this must be a monster project, but I'd watch a 2 hour version of this going into endless detail. Or a 4 part series even. The 6502 strikes me as one of the most important CPUs in history, it deserves ALL the effort and detail.
2. The segment with Bill Mensch was very short, perhaps there wasn't much to add, or he couldn't share anything new, but I wish there had been more.
3. The Z80 needs a similar video, as does the 6800/68000, as does the 8086

[Errcyco]

My grandfather was the CTO of Zilog and raised me. He helped develop the Z80.

I am very proud of him. He made life unrealistic for me.. he raised me and spent all his free time with me building PCs and listening to whatever music I found. I’ve never found anyone who holds a candle to him. Not having him around has been tough.

Knowing his work won’t ever die in some capacity makes me happy. Not this IC.. just in general with his work. He also helped GE in the 60s build their first main frame. Dude was the most modest man you’d ever meet.

Edit: I’m not going to put my families personal info out there, had no idea this comment would get any traction. Believe me if you want or don’t.

[BradHouser]

My first computer was in college in 1978: the MEK6800D2 development kit. I programmed a prototype for an automotive MPG display and a Times Square marquee, each in 512 bytes. Programming was all in assembly and hexadecimal. I would measure the frequency of the odometer and fuel sensor, divide distance pulses per second by fuel pulses per second and converting that to MPG units all using bit shifting. Storage was Kansas City standard audio tapes. My productivity improved immensely when I learned how to use the 6800 assembler on the university mainframe. I was unaware of the history of the 6502 and its connection to the 6800 at the time. It is great to hear from the people like Bill Mensch, who were hands on with some these things that are now household words. Thousands of pacemaker users are happy to know they are using some of the most tried and true processors there is.

[ACBMemphis]

At 4:38 that's me closing the VCR lid in the video "VHS VCRs Revisited" ... Big fan and honored to be mentioned/shown in an 8-bit-guy video! (First programming experience was BASIC on the Apple //e on a 6502 ...)

[mikealan]

Thanks so much for the informative videos. Your channel inspired me to transition into IT. Two years later, I’m working full time in the industry and couldn’t be happier! Your channel is the best.

[davidryle]

So many electronic music performers are very familiar with the Rockwell 6502.

[broncofun]

Dang, that interview was strange. The video feels like it is missing the part of why the chip was designed in the first place and why it had such wide proliferation.

[mistie]

I'm not surprised that he said that. ARM was developed by people who were very much connected with the 6502 world and had been involved with the various 8-bit Acorn machines. In fact the ARM 1 was developed using BBC Micros and their Tube adapters. So you could say that the 6502's influence still impacts the computing world to this day, even if you ignore the retro world!

[ThePhiphler]

6502 is a canonical piece of computer hardware, similar to classic game consoles. They will keep getting made, emulated and implemented in FPGA forever.

[kjrehberg]

Great video!
Fun fact: The 6502 is essentially a simplified Motorola 6800 implemented using NMOS with a different pinout and a slightly modified instruction set.
That's because most of its engineers came from the Motorola 6800 team!

[Dr.Dawson]

David please post that whole interview/chat. Please

[jonathancombe]

Fascinating David I learnt a lot and I had no idea that the 6502 was still being made and it makes me happy that it is. Back in the day I had a Commodore 64 and Commodore Plus 4 at home and used BBC Computers at school, all 6502 based and used to write programs in basic for them all so I understand about memory access and some of the CPU instructions. But what I never really understood is how it all fitted together. You turned on and there was a BASIC prompt and a flashing cursor but it all seemed a bit magic as to how that all happened. I never knew about how memory was addressed and stuff like chip select lines. Between yours and Adrian's channel I have learnt so much over the last few years and now understand much better how the computers of my youth actually worked.

Really enjoyed the video, thanks!

[mooniejohnson]

I *love* these breakdowns of CPUs and other chips, genuinely. Thank you for making my day! (I had a crappy week and this actually made up for it!)

[laupert]

Thank you! This was one of the most interesting 8-Bit Guy videos I watched in a long time. The only thing is that it kind of left me longing for more. Also, I expected a bit more of the Bill Mensch interview. I appreciate the effort that goes into making a video like this, but if it was up to me it could be at least twice as long without being boring. Would love to see more of this!

[grafxgear]

10:50 The TurboGrafx/PC Engine's HuC6280 (A variant of the 65SC02) runs at 7.16 MHz & in 1987 may have been one of the fastest 6502 variants. You mentioned the SNES and Apple IIgs use the 65c816 a "16 bit" variation which may make them a bad benchmark. Where the TG16/PCE CPU is closer to the 8 bit 6502. 

11:35 Although the TG16/PCE had a few RAM expansion HuCards used by the CD-ROM attachment, there were no cartridge based enhancement chips ( 11:11 ) such as those used in SNES games. The TG16/PCE 65SC02 does make use of a video controller (HuC6270) and a color encoder (HuC6260) which certainly do some heavy lifting, but I still think the TG16/PCE would be a very good showcase of what the 6502 can do. 

Oh, and there is a mouse available if someone decided to port some games over.

[nezbrun]

You got tantalising close to giving away a key reason why the 6502 was so popular, and that's that it leaves the bus available for video half the time in a predictable way. By luck (or judgement?) one clock cycle equalled one character time on the CRT, so one half of the cycle the CPU guzzled data, and the other half was left to video. Essentially it gave way to an early form of DMA.

This wouldn't work on a Z80 as it doesn't have a predictable bus, so instead you have to implement other segregated ways for video.

[mikes]

I have been a subscriber for a couple of years and come here every so often when I'm on Youtube . I have many other channels that I watch for different topics but I always enjoy spending time here as in this video. I remember all the hardware that used the 6502 back then so it's like a trip down memory lane. You put your videos together in such a way that makes them very enjoyable to watch and this one is no exception. Thanks a lot for this and please keep giving us the great content that you have been providing.

[ForzaJersey]

@The8BitGuy You do an excellent job on these computer tech explainers. You provide the best quality videos of this type on YouTube. Great job buddy!

[tonybarnes]

I got my game dev career start on the Apple II, back in 1983 and coded the 6502 on the Apple, Vic-20, C64, Atari 8's, etc. until moving to 68000 on the ST, Amiga and Sega Genesis. 40 years later and I kind of miss the 6502 and regardless of the struggle and limitations, there was something really "fun" about getting things working back then vs. now.