Here are the resources about the 6502 CPU and its history.
* [MOS Technology 6502 - Wikipedia](https://en.wikipedia.org/wiki/MOS_Technology_6502) - Comprehensive overview of original 6502, ROR instruction timeline, development history
* [WDC 65C02 - Wikipedia](https://en.wikipedia.org/wiki/WDC_65C02) - Details on 65C02 development timeline (1981-1983), technical improvements
* [Ricoh 2A03 - Wikipedia](https://en.wikipedia.org/wiki/Ricoh_2A03) - Nintendo NES processor details, decimal mode removal, sound generation
* [Nintendo Entertainment System - Wikipedia](https://en.wikipedia.org/wiki/Nintendo_Entertainment_System) - Famicom release date confirmation (July 15, 1983)
* [MOS Technology 6502 - Computer History Wiki](https://gunkies.org/wiki/MOS_Technology_6502) - Early ROR bug details, pre-June 1976 CPUs, KIM-1 information
* [2A03 - NESdev Wiki](https://www.nesdev.org/wiki/2A03) - Technical specifications of Nintendo's 2A03 processor
* [6502 Instruction Set - Masswerk](https://www.masswerk.at/6502/6502_instruction_set.html) - Rev. A details, ROR instruction analysis
* [Development of the MOS Technology 6502: A Historical Perspective](https://www.embeddedrelated.com/showarticle/1453.php) - Detailed development timeline, transistor counts, process information
* [The Rise of MOS Technology & The 6502](https://www.commodore.ca/commodore-history/the-rise-of-mos-technology-the-6502/) - Chuck Peddle interviews, WESCON 1975 launch details
* [Chip Hall of Fame: MOS Technology 6502 Microprocessor - IEEE Spectrum](https://spectrum.ieee.org/chip-hall-of-fame-mos-technology-6502-microprocessor) - 1975 release confirmation, Apple computer usage
* [When did the 65C02 become available? - Retrocomputing Stack Exchange](https://retrocomputing.stackexchange.com/questions/11497/when-did-the-65c02-become-available) - 1983 release date evidence, Softalk magazine references
* [Were there 6502 revisions B and C? - Retrocomputing Stack Exchange](https://retrocomputing.stackexchange.com/questions/27529/were-there-6502-revisions-b-and-c-and-what-were-they-like) - Revision A vs later revisions, ROR instruction timeline
* [Interesting Video about 6502 "broken" ROR - nesdev.org](https://forums.nesdev.org/viewtopic.php?t=24484) - Modern research on ROR "bug" vs intentional omission debate
* [How to test a ceramic 6502 for the ROR bug? - Applefritter](https://www.applefritter.com/content/how-test-ceramic-6502-ror-bug) - Expert community discussion on ROR implementation theories
* [Measuring the ROR Bug in the Early MOS 6502](https://www.pagetable.com/?p=406) - Actual testing of early 6502 chips, KIM-1 from week 51 of 1975
* [Were any Apple 1s sold with non-ROR 6502s? - Retrocomputing Stack Exchange](https://retrocomputing.stackexchange.com/questions/14005/were-any-apple-1s-sold-with-non-ror-6502s) - Timeline correlation between Apple-1 production and ROR fix
* [27c3: Reverse Engineering the MOS 6502 CPU](https://www.youtube.com/watch?v=fWqBmmPQP40) - Technical presentation on 6502 die analysis and reverse engineering