tim lindner's personal blog

tlindner

The Write Protect Problem

An interesting bug appeared on MAME Testers recently. The bug linked here is really simple. OS-9 wont boot on a copy protected disk image. The solution also was simple: properly emulate the delay between issuing a write command, and the INTRQ that happens when the…

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tlindner

CoCo Max III Hi Res interface

Thanks to a few friends I've been able to upgrade my hi-res tester to support the CoCo Max III interface. It is a device similar to the Tandy Hi-res interface, but is triggered differently. Here is what MAME is doing as of today for the…

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tlindner

Tandy Hi-Res Joystick Interface

I was recently told about a bug in MAME's implementation of the Tandy Hi-Res Joystick interface. The author of C-III Pages (an early desktop publishing application for the Color Computer) discovered the mouse cursor would only go 7/8th across the width of the screen. This…

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tlindner

Color Disk EDTASM Symbol Table

The Color Disk EDTASM assembler has the option of writing a symbol table to the end of binaries it produces. You enable the feature by including the /WS switch during assembly to disk. The symbol table can be used by the stand alone ZBUG debugger.

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tlindner

Salient Assembly Episode 1

https://www.youtube.com/watch?v=dxwmPFIUpLY Welcome to Salient Assembly. The show where we deep dive into a very specific 6809 assembly language topic. Today we're talking about calling subroutines. Subroutines are a very important aspect to programming. When ever you find yourself needing to do the same thing in…

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