--- title: "Old Vintage Computing Research: 6o6 v1.1: Faster 6502-on-6502 virtualization for a C64/Apple II Apple-1 emulator" url: https://daily.dev/posts/old-vintage-computing-research-6o6-v1-1-faster-6502-on-6502-virtualization-for-a-c64-apple-ii-appl-poi3fwxyw source_url: https://oldvcr.blogspot.com/2026/03/6o6-v11-faster-6502-on-6502.html type: article source: "Two Stop Bits" published: 2026-03-31T04:24:37.357Z updated: 2026-03-31T04:25:09.487Z tags: ["infrastructure", "assembly"] reading_time: 34 upvotes: 1 comments: 0 language: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Old Vintage Computing Research: 6o6 v1.1: Faster 6502-on-6502 virtualization for a C64/Apple II Apple-1 emulator **[Two Stop Bits](https://daily.dev/sources/twostopbits)** · 34 min read · 1 upvotes · 0 comments ## Summary 6o6 v1.1 is a performance update to a 6502-on-6502 virtualization library written in 6502 assembly. Key improvements include a fast path for zero page stores (in addition to loads), trimmed instruction dispatch overhead, and better IRQ/BRK handling. Benchmarks show a 2.6% reduction in host instructions needed to pass Klaus Dormann's 6502 validation suite, dropping from 52.3 to 51.0 host instructions per guest instruction. To celebrate Apple's 50th anniversary, the author built VA1, an Apple-1 emulator running on a Commodore 64 or Apple II using 6o6. The post also surveys the history of Apple-1 emulators on 8-bit hardware, covering implementations for the Apple II, SAM Coupé, and Commodore 64, comparing their accuracy and trade-offs. Future plans include fast paths for stack operations and a dynamic page table system. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [zajo/appler: Apple \]\[ emulator for MS-DOS, written in 8088 assembly](https://daily.dev/posts/zajo-appler-apple-emulator-for-ms-dos-written-in-8088-assembly-xoe8n5s8m) · Two Stop Bits · 0 upvotes · 0 comments - [GitHub - MemoireMorte/Memo-1: A simple 6502 based computer](https://daily.dev/posts/github---memoiremorte-memo-1-a-simple-6502-based-computer-40ph7iwng) · Hacker News · 0 upvotes · 0 comments - [os8088 -- a Mac-style GUI OS for the IBM PC XT](https://daily.dev/posts/os8088----a-mac-style-gui-os-for-the-ibm-pc-xt-5eeukkqfl) · Hacker News · 0 upvotes · 0 comments - [V86 x86 Emulator](https://daily.dev/posts/v86-x86-emulator-qfvofvfug) · Two Stop Bits · 0 upvotes · 0 comments --- Tags: [#infrastructure](https://daily.dev/tags/infrastructure), [#assembly](https://daily.dev/tags/assembly) [View this post on daily.dev](https://daily.dev/posts/old-vintage-computing-research-6o6-v1-1-faster-6502-on-6502-virtualization-for-a-c64-apple-ii-appl-poi3fwxyw)