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Message: 5005

Author: john_elliott_uk

Date: 02/11/2005

Subject: Re: Hex-editors for TAP files / Disassemblies

 

--- In manicminerandjetsetwilly@yahoogroups.com, andrewbroad
wrote:
I had no

> difficulty in editing the original JSW (JETSET.TAP) as John
> described (21 45 45 -> 21 42 06, and 21 07 07 -> 21 06 42).
>
> However, this example only works because it happens not to break the
> checksum of "Bytes: jsw.js2".

JSW.JS2 certainly isn't the original filename :-)

> So whenever you edit a TAP file in a hex-editor, there's a 255/256
> chance that you'll break the checksum of the Spectrum-file you're
> editing (this is not an issue for SNA files, which have no
> checksums).

And this is why I didn't mention it; I was hex-editing a snapshot.
+3DOS files don't have this sort of checksum so they're safe to be
hex-edited as well.

 

 

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