But even there – even on an Intel machine, even under Snow Leopard – I can run an older Mac OS, enjoy my older applications, and read and edit my older documents, by using SheepShaver. But all of that is a lot of trouble, because I’m not usually using those machines I’m usually using my Intel-based Mac mini, and running Snow Leopard. I also have two PowerPC-based Macs that run Tiger and therefore have Classic.

For certain applications that won’t run properly even under Classic, I have several ancient (by computer standards) machines that can actually boot into Mac OS 9. If, like me, you still have an older application or document that you’d occasionally like to open, what can you do? I actually have three different approaches. Classic reached the end of its life in Mac OS X 10.4 Tiger later versions of Mac OS X don’t include Classic, and Classic doesn’t run on Intel machines at all. But this solution was fated not to last forever. To solve this problem, Apple tided its users over with Classic, an environment that emulated Mac OS 9 within Mac OS X. Were users doomed to lose access to all their older applications and documents? Recent Mac OS 9 applications that had been “Carbonized” might run natively under Mac OS X, but older applications certainly would not. Mac OS X was a completely different operating system from its predecessors (Mac OS 9, Mac OS 8, System 7). In the run-up to the original release of Mac OS X, users were justifiably worried about compatibility.

#1578: Apple delays CSAM detection, upgrade Quicken 2007 to Quicken Deluxe, App Store settlement and regulatory changes.

Apple lawsuit decided, Internet privacy limitations, combine Mac speakers

#1579: Apple “California Streaming” event, OS security updates, Epic Games v.

#1580: iPhone 13 and iPhone 13 Pro, Apple Watch Series 7, redesigned iPad mini, and upgraded iPad, plus iOS 15, iPadOS 15, watchOS 8, and tvOS 15.

smart displays, iOS 12.5.5 and Catalina security update, iPhone 13 problem with Apple Watch unlocking

#1581: New Safari 15 features, Center Stage vs.

#1582: iOS 15.0.1 and iPadOS 15.0.1, Apple Watch Series 7 dates, cautionary tale about backups, using Live Text and Safari extensions.

The load field allows you to enter not only numeric (hexidecimal) values, but text data and even instruction pneumonics with its built-in mini-assembler. The right panel shows the raw memory contents of the Simpleton X. The center section is displayed from highest to lowest memory location and tracks the stack pointer (which grows downward in memory as data is pushed onto it). The left memory display panel has an integrated disassembler so you can see what instructions the processor emulator is executing. The emulator window displays the Simpleton X's registers, several views of its memory space, and controls for setting memory and executing programs.

Instruction set resembles the MOS Technology 6502.

Supports stack- and program counter-relative addressing.

Edit processor registers or memory directly.

Run, stop and single-step programs at the processor instruction level.

Easy to use interface allows for experimentation.

Full featured emulation of an imaginary microprocessor.

This free application allows exploration of the basic operation of a microprocessor using a simplified model that is both easy to understand and yet allows for the development of small, useful programs. The Simpleton X is a microprocessor emulator and education tool.

Download Version 1.0 (click here for Simpleton X version history).

Mac os 9.1 windows emulator