Home Computing Weekly


SYS 64

Author: D.T.
Publisher: Artic Computing
Machine: Spectrum 16K/48K

 
Published in Home Computing Weekly #19

For anyone familiar with 64-column displays, the 32-column Spectrum format seems rather cramped. Here is a program to solve that. Load it, and half-width characters are printed on a 64-column basis. Even listings appear at 64 characters per line.

There was one slight snag with loading the tape - to be precise, two. First, it was found that the 16K and 48K versions were on each other's sides of the tape, and then it was found that LOAD"" was more successful than the recommended LOAD "" CODE, as it brought the initialising routine into action.

The actual conversion program lies at the top of store, taking up nearly 2K of RAM (F7A9-FF58 in 48K). It changes the interrupt mode, so that it can poke its nose into the action and perform the necessary conversions.

These appear to be the replacement of normal character shapes by half-width versions that are combined in pairs as single characters to be output.

The process is not without its difficulties. Picking up the interrupt for a fresh screen calls for the addition of PAUSE 1 after each clear screen command. Command lines at the bottom of the screen appear in small characters at normal spacing.

In general, the system works, though the narrow characters are not always as clear as might be wished. It also works on the printer, providing a PRINT action is called before each LPRINT. The character size can be switched from normal size to half size within a given display, and for new Basic programs it gives useful added flexibility of presentation.

D.T.

Other Spectrum 16K/48K Game Reviews By D.T.


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  • Venture Front Cover
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  • Everest Ascent Front Cover
    Everest Ascent
  • The Visual Processor Front Cover
    The Visual Processor
  • Ground Attack Front Cover
    Ground Attack
  • Race Fun Front Cover
    Race Fun
  • Devil's Revenge Front Cover
    Devil's Revenge
  • Leopard Lord Front Cover
    Leopard Lord