Re: A86: Re: LCD stuff
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Re: A86: Re: LCD stuff
>> By the way, how much power does the processor consume when the calc is
>> 'off'? I looked up the halt instruction in the z80 data book to try and
>> resolve an old dispute with a friend of mine over whether it is ever
>> truly off or not (off as in no power usage). I found that the halt
>> instruction waits for an interrupt, during which time it runs a
>> continual cycle of NOP instructions internally, to maintain memory
>> refresh logic for dynamic memory chips. I don't think the 86 uses
>> dynamic memory (or maybe it does?), but the z80 still runs during a
>> halt, so therefore it must consume power, so therefore the calculator is
>> never truly turned off except when the batteries have been removed. How
>> much power does it take? If you left it off for a long time, would your
>> batts run down?
>
> This was documented on ticalc.org when it first opened. It's
> probably still there, hidden in some directory. The TI-85
> consumes 8 microamps or something like that when off.
> It will theoretically drain your AAA batteries in 350 years.
As I remember, Magnus Hagander tested the power consumption
of the TI-85 in several different states to refute the argument that
Z-Shell uses more power than the operating system. This was
way back in the old days.