This 6502 is as old as me and I test it

There is a lot of argument if the missing ROR instruction is a bug or not. Whatever it is, it was clearly intended to be there but was left out at the last minute, likely due to time constraints for the release for the CPU. Just a handful of months later an updated data sheet was released saying the instruction would be added into future versions of the chip. The ROM we wrote is able to identify (in a running system) if you have a CPU that has a non-functional ROR instruction.
--- Info
Possible TTL shift register
TI 1A5008
--- Video Links
ROM to test for the ROR bug on the Apple II:
github.com/misterblack1/6502_...
Pagetable ROR bug article:
www.pagetable.com/?p=406
A viewer @DaftdogUK discovered what this is! See Page 102:
archive.org/details/kilobaudm...
MOS 6502 by Chuck Peddle:
en.wikipedia.org/wiki/MOS_Tec...
SWTPC 6800:
en.wikipedia.org/wiki/SWTPC_6800
Frank's Channel (IZ8DWF)
/ iz8dwf
Tech Time Traveller's Channel:
/ techtimetraveller
The TV Typewriter (Shift register storage):
• The "Typewriter" That...
Link to dumped 256 byte ROM
github.com/misterblack1/6502_...
Adrian's Digital Basement Merch store:
my-store-c82bd2-2.creator-spr...
Adrian's Digital Basement ][ (Second Channel)
/ @adriansdigitalbasement2
Support the channel on Patreon:
/ adriansdigitalbasement
-- Tools
Deoxit D5:
amzn.to/2VvOKy1
store.caig.com/s.nl/it.A/id.16...
O-Ring Pick Set: (I use these to lift chips off boards)
amzn.to/3a9x54J
Elenco Electronics LP-560 Logic Probe:
amzn.to/2VrT5lW
Hakko FR301 Desoldering Iron:
amzn.to/2ye6xC0
Rigol DS1054Z Four Channel Oscilloscope:
www.rigolna.com/products/digi...
Head Worn Magnifying Goggles / Dual Lens Flip-In Head Magnifier:
amzn.to/3adRbuy
TL866II Plus Chip Tester and EPROM programmer: (The MiniPro)
amzn.to/2wG4tlP
www.aliexpress.com/item/33000...
TS100 Soldering Iron:
amzn.to/2K36dJ5
www.ebay.com/itm/TS100-65W-MI...
EEVBlog 121GW Multimeter:
www.eevblog.com/product/121gw/
DSLogic Basic Logic Analyzer:
amzn.to/2RDSDQw
www.ebay.com/itm/USB-Logic-DS...
Magnetic Screw Holder:
amzn.to/3b8LOhG
www.harborfreight.com/4-inch-...
Universal ZIP sockets: (clones, used on my ZIF-64 test machine)
www.ebay.com/itm/14-16-18-20-...
RetroTink 2X Upconverter: (to hook up something like a C64 to HDMI)
www.retrotink.com/
Plato (Clone) Side Cutters: (order five)
www.ebay.com/itm/1-2-5-10PCS-...
Heat Sinks:
www.aliexpress.com/item/32537...
Little squeezy bottles: (available elsewhere too)
amzn.to/3b8LOOI
--- Links
My GitHub repository:
github.com/misterblack1?tab=r...
Commodore Computer Club / Vancouver, WA - Portland, OR - PDX Commodore Users Group
www.commodorecomputerclub.com/
--- Instructional videos
My video on damage-free chip removal:
• How to remove chips wi...
--- Music
Intro music and other tracks by:
Nathan Divino
@itsnathandivino

[@ShukenFlash]

I just watched a video by TubeTime where he delved into this and found that it wasn't a bug but rather was intentionally just completely left off the chip to make it as simple as possible. So more of an oversight of how important that instruction could be. He was able to find one with the die exposed and confirm that the transistors for ROR just plain didn't even exist in the early version.

[@mraaronfrancis]

The 1st revision of the 6502 doesn't have a bug, your tittle is wrong; as Chuck said "it worked the first time" the ROR function was never implemented by design. As you said ROR was never written in the instruction set..

[@NNokia-jz6jb]

Never change the intro tune.

[@davidanderson557]

I have a white 1976 cpu in the basement along with the Jameco receipt for $75 for it and the 6522 pia I bought in high school my sophomore year. I lived in PA not far from MOS fab. I called and an engineer sent me programming manuals and data sheets. Wire wrapped it up and had a tic tac toe program working on it using an old point of sale terminal. Later ran tiny basic on it in college. Fond memories.. I will probably dig it out when I retire in 3 years. But your video made me remember the gogo days of home computers

[@miltonhowe2556]

Adrian literally teared up over a novelty microchip - with a fatal flaw no less. I love it!

[@Neodra]

I work in E-Waste ... I see things like this all the time and have to take them apart to sort the parts, that board would have been thrown right in the low grade box. I try and keep an eye out for special things, but I am sure I don't always recognize that it's special. I am able to save a few things but I can't save it all. I rationalize a lot of it by saying to myself if we didn't recycle it nothing would be rare. :)

[@benthere8051]

The AY5-1013 is a UART. - Jim Ferguson

[@Cincinnatijames]

Looking at ebay solds, a 3975 dated 6502 sold Buy it now for $1500. A 1976 6502A sold for $1450.

[@RetroGamingWithEdgarRivera]

I'm glad that you didn't throw away because imagine the regrets afterwards and like Indiana Jones said "it belongs into Museum". Very impressive since I never seen this very early version of MOS 6502 before since only the later version of the Chip especially for the one of the most if not the most popular CPU of all time for 8 bit Computers. What a great find my friend.

[@petesapwell]

Truly Adrian when Franks program (iz8dwf Hi Frank) popped up declaring this was in fact a bugged MOS 6502…Man I burst into tears…I’m surprised you contained your exposure. Simply wonderful…

[@kd7swh]

I love when Adrian is at a loss for words. I'm so thankful that he takes the time to make these videos. It's more than simple nostalgia. Many of us grew up loving these 8-bit systems too and the memories are reminders of moments of joy and the learning that came from experimenting.

[@memadmax69]

Damn dude, whoever built that box really knew their stuff.

[@costa_marco]

Your reaction was the nicest thing to watch. I really enjoy your channel. Keep up with the good work. Rest assured that it is really greatly appreciated.

[@KiraSlith]

A first revision MOS 6502 from the first year of production. You're not kidding, binning that would've been a tragedy, that thing belongs in a museum display!

[@MobiusHorizons]

This is so cool. I appreciate how you were able to convey the importance of the discovery to people less well steeped in 6502 lore. That is a really awesome discovery, and even more awesome that it runs (aside from the bug) correctly. Thanks so much for sharing.

[@stevehauser7486]

Adrian, just found your channel and haven't looked at your other videos yet but I just had to comment. You have taken me back to 1975 where at that time we were programing industrial controllers with paper tape readers. When the 6502 came out a whole new digital age was launched in basements and garages, it was a magical time. Thank you for sharing this story for this old man.

[@jamieangus-whiteoak3656]

I loved this @adrian! I was studying electronics in 1974-1977, and then did a PhD in computer design.

[@nezbrun872]

AY-5-1013 is a UART from General Instruments, which eventually became Microchip, famed for their PIC line on microcontrollers. I used these UARTs extensively in the 70s, they were ubiquitous in those days.

[@gregshadoan4049]

I remember the times when you could go down to Radio Shack and get raw boards and etching to make your own circuit boards. Those were the days, really Miss the old Shack :(

[@cjheeley]

I've just started watching the video and looking at the box that Adrian nearly threw away. At first glance it looks like the box is "The Internet" as seen on the British Channel 4 comedy programme The IT Crowd 🌐 😂 Cool to see an early 6502