| readinglist | |
|---|---|
| author | Bob Altemeyer |
| title | The Authoritarians |
| summary |
A highly accessible and frankly enjoyable introduction to authoritarianism, written by someone who has studied the topic for decades. |
| status | read |
| subjects | politics |
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6502 simulator
Purpose
This project is primarily an exercise to prepare for a more in-depth project. Inspired by modern Apple II expansion cards like the V2 Retro Computing Analog card [1], we wish to design a microcontroller-based card for future experimentation, the eventual goal being an emulated Z80 softcard. We know this is an achievable goal, but it seems prudent to try writing a PC-based CPU simulator first. We have selected the 6502 as our target for its low instruction count, simple architecture, and variety of addressing modes.
Our goals are as follows:
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a SIMH-like console interface with memory/register editing, breakpoints, disassembler, and single-step execution
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simulated RAM, ROM, and I/O devices with memory mapping and bank switching
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realistic timing
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a portable and general core
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extensible for future GPIO operation
This is not intended to be able to simulate a full Apple II, NES, or similar 6502-based device.
Design
CPU core
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registers
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fetch-decode loop
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hold states and breakpoints
Simulator console and debugger
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commands
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breakpoint management
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limitations
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I/O devices