Re: comp.sys.apple2 Frequently Asked Questions (FAQ) part 2/3

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

In article spec@vax2.concordia.ca (Mitchell Spector) writes...
>
>    Actually the "Blackout" virus installs itself in the battery backed
>RAM used for the clock/Control-Panel settings. In otherwords, switching
>the main power off will not rid you of it, making it seem like your IIgs
>has experienced a hardware failure. I caught it once or twice, a certain
>demo released in 1992 seemed to have a copy of the virus on it. The virus
>is harmless, but certainly a major annoyance.

    Oops, that wouldn't be possible as there is only a few bytes RAM
for the Control Panel settings. What I _meant_ to say was the Blackout
virus hides on disk, but uses a counter (one byte?) to check how many
times the disk has been booted. When the counter reaches a certain 
number, the program on disk then changes the bytes in the Control Panel 
and then saves them (black text, background and border, sound-level zero, 
Startup device RAM Disk).

    So it saves the _results_ of the virus to battery RAM, the only 
actual thing it copies there is the counter byte to trigger it (just
a simple number like '4', '7' or such). Some programs like Photonix
make use of an unused byte in bRAM so it remembers how many disks 
you've copied. Sorry about any confusion my original post may have 
caused...

Mitchell Spector
spec@vax2.concordia.ca