Re: DragAsprite

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#46

From: Mik Davis
Date: Tue, 03 Nov 1992 10:47

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mhardy@acorn.co.uk (Michael Hardy) writes:
: 
:    REM Toggle state of DragASprite bit in CMOS
: 
:    REM Read byte
:    SYS "OS_Byte",161,&1C TO ,,byte%
:    REM EOR byte with mask for bit 1
:    byte% = byte% EOR 1<<1
:    REM Write byte back again
:    SYS "OS_Byte",162,&1C,byte%
:    END
: 
: You *must* use the OS_Byte calls, otherwise the checksum byte will become
: incorrect. This byte is calculated on a power-on reset, and then maintained
: by the OS_Byte calls (in other words, they don't recalculate it, but merely
: update it in a manner that is appropriate to the changes made).
: 

  What does this module mentioned a while back do that's different to this?
and does it do it properly? and is it on Newcastle yet?


-- 
___________________________________________.
 Mik Davis at Aston University, Birmingham |   .  .  __          .
                                           |   |\/|  | \  _,_  _  _
E-Mail: davism@uhura.aston.ac.uk           |   |  |. |_/ |_| \/ |/_'

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Path: arc1-ca.pugleaf.net!sparky!uunet!pipex!warwick!sunserver1.aston.ac.uk!uhura!davism

References: <19957@acorn.co.uk>

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Path: arc1-ca.pugleaf.net!sparky!uunet!pipex!warwick!sunserver1.aston.ac.uk!uhura!davism
From: davism@uhura.aston.ac.uk (Mik Davis)
Subject: Re: DragAsprite
Message-ID: <1992Nov3.104734.17047@aston.ac.uk>
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Date: Tue, 3 Nov 1992 10:47:34 GMT
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