Re: CDA removal?

[spec@vax2.concordia.ca (Mitchell Spector)]

>In article Clairemont High School  <clairmnt@n2.net> wrote:

>If memory peeker and visit monitor are present as CDAs in a GS,
>are they taking up memory?

    Yes, but only several bytes of memory (even though both of
the CDA's are stored in ROM).

>If so, how does one remove them?

    The easiest way is to boot into the Finder and load up the
graphical Control Panel called "SetStart". There you will find
an option checkbox to 'Enable programmer CDAs'--which needs to
be deselected. The next time you turn on the GS, the two CDA's
should no longer be in the Classic Desk Accessory menu.

    However, if they're still there and seem to be permanently
stuck, then you probably have one of the ROM 3 boards with a
not too well known bug (I have one of these actually). The
problem has to do certain kinds of 64Kx4 DRAMs used in the
'Slow RAM' bank. Upon a cold-boot, memory at bank E1, at the
address 017D, _should_ have the value of '00'--but some chips
start up in a random state and give a value like 'FF'. This
will cause the GS to install the CDA's *always* because it
checks at that address when you start up the machine. This
is going from memory, so I might be a bit fuzzy on details.

    In any case, the solution is simple. I had someone
(I think it was Jay Krell) write an INIT file that would 
fix this problem. It changes the value at E1:017D and then
temporarily forces the the two CDA's out of the menu (plus
'Alternative Display Mode' CDA, since I never used that :).
The next time I warm-boot it gets rid of them completely,
since the value has changed (not permanently though, so
I always need to keep the INIT installed). Incidentally,
it's called "BadRom3Bit". I can upload it to the Ground
FTP site if your having trouble finding it. 

Mitchell Spector
spec@vax2.concordia.ca