Errors - redcode/ZXSpectrum GitHub Wiki

Author: Gimeno Fortea, Pedro
Release date: 1998
Links: Website
Download: zip _^(hosted) - zip _{^{(original URL)}}

This program generates all possible errors. Here are a few notes:

• Error 8 is provoked using a hack, since there's no 'wrong' code that produces it in absence of I/F I. Basically, it makes the input routine for the 's' channel (Screen) point to an end-of-file routine. Note that the hack is not reversible. (See also the note about Error J in 128K mode below).

  Also, there's something special about Error 8, in the sense that I couldn't avoid the K cursor being shown after the error message. That's a Speccy bug, in fact, also shown when you cause Error J by entering e.g. INPUT #3;a$.

• The following errors need the user's assistance to be shown:

  • D BREAK - CONT repeats
  • G No room for line
  • H STOP in INPUT
  • L BREAK into program
  • N Statement lost (this has to be caused totally by the user)
  • R Tape loading error (This can't be caused by the program, obviously, and is generated using POKE 23610,26)

• The following are not actually errors but there are strings for them, and are generated using POKE 23610,errorcode:

  • S ,
  • T (C) 1982 Sinclair Research Ltd

• Error "O Invalid stream" trusts channel 15 not being open.

• Error "G No room for line" uses the system variables RAMTOP and VARS to find out how much memory is available and fill most of it before asking the user to enter the line required to generate the error.

• Error F (Invalid File Name) is not produced with Interface I. I know little about I/F I so I couldn't figure out how to produce it in both cases (with and without I/F I).

• Error G generation crashes the 128K Spectrum when in 128K mode. It works fine in 48K mode.

• Error J is not produced in 128K mode with channel #3. If the (irreversible) error 8 has not been produced previously, then changing the channel to #2 makes the error show correctly.