[author : Keneth A. Simons] #Mathematics #Book

Extract : «  SUMMARY: The N-log is so defined that it is a simple positive integer used to represent any number, with any required precision. No suffixes, prefixes, exponents or decimal points are needed to allow symbolizing the entire range of numbers encountered in scientific computations. N-logs are particularly useful with digital computers, eliminating the need for floating point routines and exponential notation. A procedure is described that allows finding the N-log of the sum or difference of two numbers, when the N-log of each is known, without converting from N-logs to numbers or vice-versa. [...]  »

[author : David W. Friedman] #Listing #Assembly #GameChance #Graphics

Extract : «  Eiko and I were spending the year-end holidays quietly at home with my word-processing-oriented North Star patiently waiting for the next major copywriting assignment which is how I earn our keep. We had been recounting the fun of playing the slot machines in Macau and the Philippines when she challenged me to put the game up on the computer. I agreed on the condition that she help with the graphics and off we went.

THE HARDWARE

A North Star Horizon II double-density system with 56K of RAM, a Vector Graphics Flashwriter I video board at EOOO, a 12V TV converted to a monitor and an 80-column frictionfeed Teletype 43. Other video boards may have the same or similar graphics provisions but I know of at least two which don’t, so you’ll have to check carefully or else rewrite the graphics routines to match what you have. [...]  »

[author : Leonard E. Garcia] #Listing #Assembly #Programming

Extract : «  QUICK-KEY is an 8080 assembly language program that generates North Star BASIC commands and statements from pre-stored text in memory by using a two key command.

The program also allows a user to enter and define any text that will be sent to the North Star BASIC interpreter (or any system program) upon hitting a special sequence of keys.

Commonly entered routines, answers to prompts, even entire routines can be entered into the program and sent to any program that calls for a character from the terminal by just hitting two keys. A user no longer needs to enter the same information again and again. [...]  »

[author : Gary D. Gaugler] #Listing #Fortran #Education

Extract : «  This program is designed to be the basis of a foreign language instruction system. When run on a single-user system, the user can practice, learn and build a foreign language vocabulary. When installed on a multi-user system, many students can simultaneously use the program. Further, each student user can be practicing a language different from the other users. [...]  »

[author : Lacliman Sippy] #Listing #Assembly #Interface #Printer

Extract : «  What is wrong with this relatively inexpensive feature loaded printer? I ask this question because I have read so many articles or letters from disappointed or frustrated owners of the WH14.1 will describe my own experience and tell you how to get the most out of it. [...]  »

[author : Freeman L. Moore] #Listing #Assembly #Algorithm #Programming

Extract : «  Computer programming: is it merely writing a set of instructions to accomplish a specific task? I would hope we agree that writing the set of instructions can be a very involved process—working with such things as clarifying the problem statement, developing an algorithm, flowcharting, testing, debugging, documentation, and writing the code or instructions. Quite often, one considers a program completed when it produces the correct results. This may be acceptable for programs which are used only once; but for production jobs which are kept and used again, good documentation is essential.

Documentation of a computer program should consist of the problem statement, operating instructions, flowcharts and sample input and output, among other items. Some features are part of what might be referred to as a “user’s manual,” while others belong to a “programmer’s manual.” Ideally these two manuals will be kept separate since it should never be assumed that the user is capable of programming, and that the programmer tends to forget the needs of the naive user. [...]  »

[author : William D. Loughman] #Listing #Assembly #Programming

Extract : «  The standard 2000 hex address of the North-Star DOS can be an annoyance at times. Large programs starting anywhere below the DOS sometimes cannot be loaded from disk, as the DOS may be overwritten before the load is completed. There are a lot of nice programs which were not designed for use with the N * disk system.

These can be used painlessly by tacking them onto a short ‘mover’ program. MOVIT cares not where it is started. [...]  »

[author : William C. Colley, III] #Programming

Extract : «  A cross-assembler, like a normal assembler, is a program that converts human-readable assembler source code for a given microprocessor into binary machine code for the same processor. The difference between a cross-assembler and a normal assembler is this: a normal assembler program is run on the same type of processor as the output of the assembler and a cross-assembler program is run by a different processor. For example, a 6800 assembler runs on a 6800 and converts source code in 6800 machine code. This particular 6800 cross-assembler runs on an 8080 or Z-80 and converts 6800 source code into 6800 machine code.

With an appropriate cross-assembler, you can write and assemble code for another (in this case 6800 or 1802) processor using your existing (in this case CP/M) editors and floppy disks. This keeps you from having to have separate disks, disk operating systems, editors, etc. for each different processor. [...]  »

[author : Ralph Deane] #Listing #Forth #Programming

Extract : «  Once a person has used FORTH for a period of time, two deficiencies usually appear. These are the lack of floating point (real) numbers, and the absence of any string handling functions. Much of the work currently being done in BASIC could be done quicker and easier in FORTH if these two problem areas were fixed.

The area of floating point numbers has been adddressed by different groups, and Kitt Peak Observatory has published their approach in the Kitt Peak FORTH Primer. This will probably become the standard in the future.

The problem of string handling in FORTH is an area which, as yet, has received little attention. In this article I propose to outline one approach to solving this problem. In no way is this method to be thought of as a finalized standard solution to string handling. It is meant to be a starting point from which to build a unique (and powerful) string handling package. [...]  »

[author : Kenneth Drexler ] #Listing #Assembly #Display

Extract : «  If you want to get away from the slow speed, paper costs and noise of a teletype or other hard copy terminal, try a video display. Here is a 6800 video display program for use wih a memory mapped video board such as SSM’s VB1 or others using a 1K display memory.

The program has a full range of commands including: Cursor Up, Cursor Down, Cursor Right, Cursor Left, Cursor On and Off, Home, Erase to End of Line, Backspace, Screen Clear and, of course, Carriage Return and Line Feed. This displayed line and page length may be varied up to a maximum size of 64 characters by 16 lines. All data before being displayed by the program are checked against high and low masks to see if the data falls within the limits set by these masks. By changing these masks which are located in RAM, it is possible to limit the characters to a subset of the full ASCII alphabet, such as capital or lower case letters only. [...]  »