Radio ShackReseñas

This reference manual gives the technician all the information that's needed to troubleshoot and repair a TRS-80 Model I Micro Computer. Block drawings, detailed waveforms, and complete schematic diagrams are provided on fold-out pages. Actually, the schematic diagrams are printed on two, large, 35x11-inch fold-outs.

Considerable space is given to the theory of operation: CPU address lines, CPU data bus, CPU control group, system RAM, video divider chain, video RAMs, video processing, keyboard, input and output port, system power supply and Level II ROMs.

The chapter on troubleshooting aids the technician with the disassembly of the computer keyboard where the logic board and CPU are located. An exploded view makes it easy to take things apart and put them back together again.

A troubleshooting flowchart enables the technician to quickly isolate which one of 21 sections contains the probable cause of a problem. There is a separate flowchart to help the technician with CPU troubleshooting. There are also helps for troubleshooting ROM, RAM, address decoder, sync generator, power supply, ports, cassette tape recorder/player, and video display monitor. In fact, every item discussed in the previous chapter about the theory of operation is discussed again from a troubleshooting perspective in this chapter.

In the back of the manual, there is a complete parts list keyed by symbols to the schematic diagrams. There are multiple tables with line-item descriptions and part numbers for capacitors, diodes, jacks, relays, transistors, resistors, switches, sinks, sockets, crystals, integrated circuits, RAM kits, and main printed circuit board.

DeskMate Version 1.0 came packaged with each purchase of a Tandy 1000 PC in 1984. For instance, there was (1) DeskMate diskette (a 360K 5.25" floppy disk), (2) DeskMate: A Reference Manual, (3) DeskMate: A Quick Reference Guide, and this (4) Introduction to the Tandy 1000: A Tutorial to DeskMate.

DeskMate provided a CGA windows environment long before the earliest version of Microsoft Windows made its appearance in the marketplace. DeskMate was an integrated software program, not an operating system.

Its features included Main Menu, Text, Filer, Worksheet, Calendar, Alarm, Telecom, Phone, Mail, and Host.

DeskMate Version 1.0 came packaged with each purchase of a Tandy 1000 PC in 1984. For instance, there was (1) a DeskMate diskette (a 360K 5.25" floppy disk), (2) an Introduction to the Tandy 1000: A Tutorial to DeskMate, (3) a DeskMate: A Quick Reference Guide, and (4) this handy guide, DeskMate: A Reference Manual.

DeskMate provided a CGA windows-like environment long before the earliest version of Microsoft Windows made its appearance in the marketplace. DeskMate was an integrated software program, not an operating system.

Its features included Main Menu (a pull-down menu), Text (a word processor), Filer (a database manager), Worksheet (a spreadsheet program), Calendar (time management software), Telecom (a communications terminal), Alarm (audible reminder of scheduled events), Phone (used to store, view, and place calls), Mail (a messaging system), and Host (allowed remote access by modem).

The Tandy 1000 was the successor to Radio Shack's TRS-80 line of computers.

These early Tandy 1000 computers had MS-DOS 2.11 built into ROM allowing the OS to boot in a few seconds.

An odd feature of the Tandy 1000 was a non-standard edge card printer connector built onto the motherboard and protruding through the rear. An adapter was needed for the T-1000 to work with a standard IBM-style printer.

The Tandy 1000 also featured a proprietary keyboard and keyboard port.

DeskMate augmented normal PC activities with its pull-down menus and interactive dialog boxes, thus simplifying many DOS operations.

Today we would call DeskMate a DOS shell and a graphical user interface (GUI). Although you could use a mouse with DeskMate, it didn't need a mouse to operate.

The hardware demands of DeskMate were minimal. It ran just fine on a Tandy 1000 with 128K RAM and one 360K 5.25" floppy disk drive. DeskMate was written in C and Assembly Language.

Contains an indexed listing of applications software for the TRS-80, including author, program description, types of media available, minimum equipment required, price, and ordering information. Contains listings for Games, Business Applications, and Home Use. Contains over 3,900 programs.

This manual assumes that the reader has already mastered Level I BASIC as presented in tutorial fashion in the Level I Manual. The Level II Manual is a reference-only manual, not a tutorial. For a tutorial on Level II BASIC, see Programming Techniques for Level II BASIC (1981) by William Barden Jr.

Level II is a far more powerful version of BASIC than Level I. It prepared me well for making the transition to the version of Microsoft BASIC that ran on the IBM XT and after that for the transition to QuickBASIC on IBM PC compatibles.

When the Level II Manual came out, the TRS-80 still loaded its programs from, and saved them to, a tape cassette. By adding an Expansion Interface to the Model I TRS-80, owners could add an additional cassette deck, a TRS-80 line printer, up to four floppy disk drives, and up to 48KB of RAM memory, all of which could be addressed by Level II BASIC and its successor, Disk BASIC on TRSDOS for floppy disks.

This workbook was used as a lab manual to teach computer programming in BASIC on TRS-80s at my college in the early 1980s. It covers the commands, operators, and statements of Radio Shack's Level 1 BASIC.

This workbook was used as a lab manual to teach computer programming in BASIC on TRS-80s at my college in the early 1980s. It covers the features added by Radio Shack's Level II BASIC, including new system commands, program line editing, types of variables and type declarations, arrays, error codes, relational operators, logical operators, the PRINT USING statement, memory management, and string manipulation.

This collection of TRS-80 Microcomputer Newsletters includes all issues (N=20) from the first issue published in 1977 through December, 1980. Much of the early history of the TRS-80 line of microcomputers is told in these pages. I took delivery of the first Model I TRS-80 sold in Knoxville, Tennessee, in October, 1977. I read and re-read each of these newsletters as soon as they were delivered to my mailbox. Many of the subroutines and algorithms found in the newsletters were later incorporated into my BASIC programming projects.

This bundle of TRS-80 Microcomputer Newsletters includes all 1981 issues plus the 1981 index.

This 1981 manual was written for people who already have a thorough understanding of electronics and computer circuitry. Is is not a beginner's manual.

The manual contains detailed schematics and theories of operation for each major part of the Model 3 TRS-80 Microcomputer. The information in this book enabled me to design interfaces for computers in my college computer lab and to make my own repairs. Preventive maintenance was a must on the TRS-80 floppy disk drives with their penchant for dirty heads and sticky rails.

This is a handy reference was published in 1982 for looking up electronics formulas and laws, mathematical tables and formulas, amateur radio communications data, cable and copper wire specifications, and miscellaneous conversions.

Applicable to the Model 101 also.