Date   : Mon, 15 Nov 2004 17:21:35 +0000
From   : Richard_Talbot-Watkins@...
Subject: Re: ?86 and ?87

Andrew W wrote on 15/11/2004 17:07:39:

> I'm just wondering if anybody could suggest what might be interfering
> with ?&86 and ?&87. As far as I can see I'm just changing ?86 and just
> setting ?87 once yet ?87 is turning from a value of 30 into 2,5,6 etc and
> ?86 into unexpectedly large values (although that could be my code not
> doing what it should).

First off, check that you are writing to ?&86 and ?&87, rather than ?86 and
?87.  They are very different - the latter pair are in the Basic language
workspace, so it's not unreasonable to expect that they might not preserve
values you write to them.

> I'm writing a word to !84 but that should just
> set 84 and 85 should it not?

Ah, no.  !&84 (assuming you mean that) will set four bytes from &84 to &87.
There is no operator to set only two bytes in BBC Basic.

Cheers,
Rich



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