Addressing A Problem

By Paul Woodward

Originally published in EUG #11

I have an Electron with Pres Plus 1, AP4 (with ADFS 1.15 ROM), AQR, ABR, Akhter 40/80 track 5.25" drive.

I have recently started to write programs in assembler and am having difficulty obtaining detailed information regarding certain operating system addresses. In particular I want to obtain:-

  1. A full list of all operating system RAM addresses (&0000 to &0E00) with their functions, especially all addresses for interception of BREAK (&287 etc);
  2. A similar listing of ADFS RAM adresses (&0E00 to &1D00);
  3. 1770 DFS register addresses:
    Drive control register;
    Status/command register;
    Track register;
    Sector register;
    Data register;
  4. Any available technical data for the cassette port serial communication.

In addition to the usual User Guides, the books I have are:

THE NEW ADVANCED USER GUIDE (For BBC & Electron) - Dickens & Holmes
ACORN ELECTRON ADVANCED USER GUIDE - Holmes & Dickens
ASSEMBLY LANGUAGE PROGRAMMING ON THE ELECTRON - Ferguson & Shaw
ADVANCED PROGRAMMING FOR THE ELECTRON - James & Gee

I would be grateful for any help.

Paul Woodward
Eastbourne, East Sussex

If this was our dearly missed Electron User, the knowledgable editor would now be reeling off a helpful list of double-dutch which only you clever people can understand. This ain't, I'm not! Someone help please!!

Will Watts, EUG #11