Amstrad DDI-1 manual Amsdos Primer, Introduction

CHAPTER 2

AMSDOS Primer

This chapter describes AMSDOS, covering all the available commands and their uses. It details the format of filenames and provides a reference guide to the commands. Each step is illustrated by the use of examples.

Subjects covered in this chapter:

•Introduction to AMSDOS

•Disc Directory

•The format of file names

•AMSDOS file headers

•Wild cards

•An example program using AMSDOS Commands

•Reference Guide to AMSDOS Commands

•Manipulating files

•Reference guide to Error Messages

2.1 Introduction.

AMSDOS extends the AMSTRAD BASIC supplied with your CPC464 by the addition of a number of external commands and by re-defining some of the existing BASIC commands. The additional external commands are identified by the (bar) symbol and are automatically available from ROM when the DDI-1 disc interface is plugged onto the CPC464.

NOTE that where a string expression is required by an external command it must be passed a string variable address. See ERA as an example. Note also that it is not permitted to include the (bar) symbol in a REM statement.

AMSDOS allows the user to change discs freely, as long as no files are in use -in which case an error message will be displayed and there could be a loss of data if the open file was being written to.

Chapter 2.1 AMSTRAD Disc Drive & Interface DDI-1 Manual