Re: TI-82 ROM Version (Self Test)


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Re: TI-82 ROM Version (Self Test)



Elwood Gruschow wrote:
>
> Dear Craig,
>   There is no proof to the rumor that an industrial spy from the American
> Battery Sales Organization secretly deposited the "mode alpha S " code
> into the TI-8x series.   The counting is the number of passes to the self
> test.  If a calc passes the self test once it's okay.  The calc will keep
> going because the self-test defeats the auto power down feature.
>  The counting repeats after some good bianry number like 16k or 32k or
> such.  If you have a little extra money for some batteries and don't mind
> losing use of your calc for a day you could find the actual number.


I have seen a disassemblied version of the self test for the TI85, and
the
reason that calc loops the test is that the test is written in a loop.
The selftest does turn off the APD feature, but that does not make the
calc
loop special functions.


The selftest (on the ti85) first checks the RAM (writes 00 to all adrs)
then
it checks the rom, by calculating the check sums. After that it will
check
the display and keyboard.
<pre>
--
_______________________________________


Dines Justesen
Email: dines@post1.com or
       c958362@student.dtu.dk
WWW  : http://www.gbar.dtu.dk/~c958362/
_______________________________________
</pre>


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