Re: A86: Re: Timings
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Re: A86: Re: Timings
David... I know where that location is to check the batteries =)
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JBrett
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-----Original Message-----
From: David Phillips <electrum@tfs.net>
To: assembly-86@lists.ticalc.org <assembly-86@lists.ticalc.org>
Date: Wednesday, November 11, 1998 5:05 PM
Subject: Re: A86: Re: Timings
>
>Hmm, I think I'm the one who started that 174 rumor. 174 times a second is
>the value that made my clock program work accurately. But I only tested it
>once, so it probably changes with the battery power. I don't think it's
>always 174 times a second. Maybe if we could find the rom code that check
>the battery power...
>
>-----Original Message-----
>From: Dark Ryder <DarkRyder@cyberdude.com>
>To: assembly-86@lists.ticalc.org <assembly-86@lists.ticalc.org>
>Date: Wednesday, November 11, 1998 12:57 AM
>Subject: Re: A86: Re: Timings
>
>
>>
>>You also need to remember that your program doesn't get to use all 6 mil
>cycles
>>unless you disable interrupts - the 'software' interrupt runs approx. 174
>times
>>per second (or so I've heard). The easiest way to count off a second,
>>therefore, is probably to install a user interrupt that counts down from
>174:
>>
>>seconds:
>> .db 0
>>
>>.org _user_int_ram
>>user_int:
>> push af
>> ld a,(counter)
>> dec a
>> jr nz,notyet
>> ld a,{seconds)
>> inc a
>> ld (seconds),a
>> ld a,174
>>notyet:
>> ld (counter),a
>> pop af
>> ret
>>counter:
>> .db 174
>>.end
>>
>>David Phillips wrote:
>>
>>> The Z80 in the 86 runs at 6Mhz, or 6,000,000 clock cycles per second.
An
>>> instruction is measured in t-states, or time states. A 4 t-state
>>> instruction, such as NOP, would execute 1.5 million times in a second
>>> (though I have heard this is not exact, can anyone confirm?).
>>
>>--
>>Dark Ryder
>>ICQ#: 8189903
>>E-Mail: DarkRyder@cyberdude.com
>>
>>Happiness is inversely proportional to how much you want to upgrade your
>>computer.
>>
>>-----BEGIN GEEK CODE BLOCK-----
>>Version: 3.12
>>GCS/CC/ED/IT/M/MU/P/S/O/AT (!)d-? s++(+):+(++) a?--- C++++$
>>UB>L+++ P L>+++ E- W+++$ !N o? K- w(---)$ !O M(+)(-) V?
>>PS+(+++) PE-- Y PGP++ t*+(+++) 5++ X+ R*+++ tv b+++ DI++++
>>D++ G++>++++ e*>+++++ h!>++ r-(+) y**++
>>------END GEEK CODE BLOCK------
>>
>
>