Introduction
Over the past year, I have been writing an emulator for the original IBM PC Model 5150, and its slightly more advanced brother, the IBM XT M...| martypc.blogspot.com
My last few articles on bus sniffing the IBM 5150 have been building up to this one. We're going to leverage our bus sniffer and sniffer decoder to finally debug Area5150's "Lake" effect.| Adventures in PC Emulation
This is part 6 of a series of articles investigating various floppy copy-protection schemes seen on the IBM PC platform. You may wish to read the previous entries in this series:| Adventures in PC Emulation
This is part 5 of a series of articles investigating various floppy copy-protection schemes seen on the IBM PC platform. You may wish to read the previous entries in this series:| Adventures in PC Emulation
This post goes hand-in-hand with my article on Vault Corporation's Prolok copy-protection technology. Perhaps the most important historical legacy of Vault Corporation results from the lawsuit they initiated against Quaid Software, makers of the backup software CopyWrite. | Adventures in PC Emulation
This is Part 4 of a series on PC floppy copy protection methods. You can read the previous parts here: | Adventures in PC Emulation
This is Part 3 of a series on PC floppy copy protection methods. | Adventures in PC Emulation
This is part 2 of a series on PC floppy copy protection methods. You can read Part 1, covering Formaster Copy-Lock here.| Adventures in PC Emulation
A V20 CPU, courtesy of Konstantin Lanzet (CC)| Adventures in PC Emulation
In a previous article, I described a simple state machine to explain the prefetch behavior and miscellaneous observed bus delays of the Intel 8088. I now believe that the model I described there - although successful in modelling the 8088's behavior - was unnecessarily complex. There are in fact far fewer legitimate bus "delays", and they do not relate to internal state transitions. I have also slightly revised my description of the BIU's prefetching logic - I now believe that the prefetching...| Adventures in PC Emulation
My emulator has a bug. | Adventures in PC Emulation
Over the past year, I have been writing an emulator for the original IBM PC Model 5150, and its slightly more advanced brother, the IBM XT M...| martypc.blogspot.com
Entering the 16-bit Era I've been adding support for the 8086 CPU to MartyPC, and looking ahead to eventual support for the 286 . The biggest fundamental change coming from the 8088 is that the data bus width on these CPUs expands from 8 bits to 16. This ends up being a bit more complicated than I originally anticipated, but I've come to learn some interesting things about how Intel implemented the 16-bit data bus that explains some things that were long-standing mysteries to me, such as th...| martypc.blogspot.com
Preface This is Part 1 of a series of articles investigating various PC floppy protections, as I get them working in MartyPC . It assumes you have a familiarity with the structure of a PC floppy disk and the basic operation of a PC floppy drive. Thanks Thanks to NewRisingSun on VOGONS for his vast knowledge of copy-protection schemes and history, and to OBattler for his extensive knowledge of PC floppy controller operation. Formaster Corporation The Formaster corporation, headquartered in S...| martypc.blogspot.com
Entering the 16-bit Era I've been adding support for the 8086 CPU to MartyPC, and looking ahead to eventual support for the 286 . The bigge...| martypc.blogspot.com
Preface This is Part 1 of a series of articles investigating various PC floppy protections, as I get them working in MartyPC . It assumes yo...| martypc.blogspot.com
In my last article , I dodged the issue of writing a custom decoder for the 5150's bus signals to use in DSView, instead just processing the...| martypc.blogspot.com
Writing a cycle-accurate emulator for a computer system is more than just understanding all the CPU instruction timings. A computer is a com...| martypc.blogspot.com
The Book8088 is an interesting little machine. It is essentially a 1980's computer in a laptop form factor. With apologies to Sergey Kiselev...| martypc.blogspot.com
In a previous article, I revealed one of the secrets to MartyPC 's accuracy, hardware validation . To summarize, it is a method of using a m...| martypc.blogspot.com
Much has been written about the PC demo 8088MPH . If you haven't seen this demo yet, take a moment to watch it. If you're familiar at all ...| martypc.blogspot.com
⚠ This post is now outdated. Although the logic described here will correctly model the externally observed behavior of the 8088,...| martypc.blogspot.com
My emulator has incomplete implementations of the EGA/VGA cards. Since these cards share a lot of common functionality and register architec...| martypc.blogspot.com
Early in development I was looking for a utility to test my crude PC speaker emulation. I found a simple keyboard-piano program called PIAN...| martypc.blogspot.com
In the emulation world, there are a few different ways to determine if your emulator is accurate. The traditional way has been through the ...| martypc.blogspot.com
In order to accurately emulate cycle-counted demo effects such as the Kefrens bars effect in 8088MPH, or the end credits in Area 5150, there...| martypc.blogspot.com
DMA, or Direct Memory Access, is a scheme that allows peripherals access to system memory without the assistance of the CPU, which normally ...| martypc.blogspot.com
