September 27 - 29, 2019

Springfield, OH

Tandy Tech Track

The Classes


Title: Advanced Z-80 Programming

Instructor: George Phillips

Abstract: Give a general overview of where the Z-80 instruction set is fast and/or compact. Present a number of common micro-optimizations (e.g., XOR A for LD A,0) and some useful techniques for faster loops, memory copies and other common operations.


Title: Model 100 Design and Repair

Instructor: Josh Malone

Abstract: The Tandy Model 100 family are common and accessible vintage computers and make great additions to Tandy collections. However, due to their unique RAM- and LCD-based design, newly-acquired units often exhibit common problems and require component-level repairs before they will function. Based on years of repairs and repeated questions from new owners, this session will cover the design details of the Model 100 family of portable computers (100, 102, 200, and some non-Tandy variants) and demonstrate the commonly needed repairs. It will also cover strategies for "field-testing" units before purchase, as well as basic accessories you will want to investigate once your unit is working.


Title: 8" Tandy Repair, Upgrades, FreHD48 and Model I Power Supply Build

Instructors: Ian Mavric and Eric Dittman

Abstract:This course will focus on everything you need to know to get a Model II/12/16/16B/6000 up and running. It will also discuss modern upgrades including a special focus on the new FreHD48 hard drive emulator. Mav will also show you how to build a modern replacement Model I Power Supply.


Title: Tinkering with the TRS-80's I/O Bus

Instructor: Arno Puder

Abstract: The I/O Bus allows external devices to be connected to a TRS-80 computer. Examples are the popular FreHD that simulates an external hard disk or TRS-IO that adds general I/O capabilities such as networking to a TRS-80 machine. This workshop will explain the functionality of the I/O Bus and how to use off-the-shelf integrated circuits to create a simple I/O device that can be connected to a TRS-80. We will provide a crash course in TTL logic and how to use a logic analyzer to debug your design. To round things up, we will explain how TRS-IO performs its magic.


Title: CoCo Floppy Disks in a High-Tech Vintage World

Instructor: Paul Fiscarelli

Abstract: In the modern era of solid-state technology, data storage is something that is often taken for granted with media devices now measured in trillions of bytes. Not too long ago, the limitation of our available data storage was measured in tens-of-kilobytes - hardly enough capacity for a single web page today. This session will take a look at the present significance of floppy disks, who is using them, and why they are still relevant to the vintage computing community. With a focus on the TRS-80 Color Computer, we will explore tools which enable the cataloging, examining, interaction, and searching of virtual disk image content. Lastly, we'll also investigate methods of archiving forgotten data from physical floppy disks - even in cases where disks may be considered unreadable by traditional retrieval methods.