COS-310 ISAM and Screen Handler, Version: August 1982
8-932

Author: Rudi Stange, Digital Equipment Corporation, Munich, Germany

Operating System: COS-310 V5 through 8.02 Source Language: DIBOL
Memory Required: 24KB Special Hardware Required: RX01 or RX02
Drives Keywords: ISAM; Utilities - COS-310

Abstract: The subroutine (SRIND) presents an Index Sequential Access
Method. This subprogram divides the total number of blocks in file by
two, and determines if the block searched for is located in the upper or
lower half. This half is again divided by two, and determined if the block
searched for is located in the upper or lower half of the newly divided part
and so on, until the desired block is found.

The screen handler (STDIAC) is a subprogram for easy handling of
numeric or alphanumeric data on the display. A maximum of 15 fields
(may be expanded) of 1 to 80 characters each may be worked on at a time.
Return and backspace key allow easy closing and opening of any field on
screen at random. Fields may be exempt from modification. Any number
of decimal formats may be used with complete decimal control. Line feed
key skips out of the screen, delete and ctrl/u keys work as usual, ctrl/x
one field after another (as return), but does not leave the screen.

A complete menu controlled address filing system is furnished with heavy
comments to illustrate the use of both subroutines. An introduction to
users and to programmers is supplied. All programs are presented in
binary as well as in DIBOL source language on RX01 floppy. The floppy
is to be inserted into drive 0 and an empty floppy into drive 1. Depressing
the start key will show the menu on the screen.

Note: When used with COS-310 V9, minor changes for the sort definitions
become necessary.

Documentation on magnetic media.

Media Service Charge Code: Floppy Diskette (KA) Format: COS-310
Catalog: June 1985