#Edito

"Dueling DOS"

TABLE OF CONTENTS

[author : Dave Cortesi]

Author Cortesi sets two operating systems for the IBM Personal Computer head- to-head. They are measured against each other, as well as compared to CP/M-80. Amplifications, rebuttals, amendments and corrections sent by readers will be part of a follow-up article later this year.

[author : Ray Duncan]

Not all details of the PC’s high-resolution graphics are clearly documented in the official manuals. This article is confined to discussion of the color/graphics interface in hi-res text and graphics modes. Included are a memory map, line generator subroutine, graphics dump routine and more.

[author : Robert Blum]

DDJ #66 presented an article covering a number of commonly used check digit systems. This short piece serves as an addendum to the original, and may help readers perform a self-check for possible dubious conclusions they may have formed.

[author : H. T. Gordon]

Last month saw a description of this simulator. The current installment presents all the code needed to allow a COSMAC 1802 to run PDP-8 code. Get it running — the author will be contributing some useful applications software as well.

Underground lore reveals how an approximation algorithm can be designed to yield a value with either an absolute or relative error less than a pre-set value, over a defined interval of the numerical input...

[author : H. T. Gordon]

[author : Matthew Halfant]

This powerful language puts down roots in the 9900, thanks to author Halfant. Follow him down the trail to his implementation on this 16-bit machine.

[author : Gene Head ]

[author : D. E. Cortesi]

[author : Michael Wiesenberg]

[author : Robert K. Funkhouser]

Word Processors for the IBM PC

[author : Jerry Crimmins]

[author : George W. Jolly]

[author : Chuck Ballinger]

[author : Robert Ashworth]