On Thu, 16 May 2019, Dwayne Reid wrote:

> Hi there, Mike.
>
> I think your routine is brilliant!  I'm not seeing any flaws and I'll
> give it a try tomorrow.
>
> Many thanks!
>
> dwayne
>
>
> At 01:34 AM 5/16/2019, Mike Rigby-Jones wrote:
>> We've not had a coding challenge in ages, I really miss those days!  I'v=
e
>> not used PIC assembler for a long time so I'm pretty rusty, so there may=
 be
>> a bonehead mistake in this:
>>
>> ; Input in ACC0
>> ; 12 cycles, no temp variables
>>
>> clrf  ACC1   ; Clear MSB
>> movf  ACC0,w ; save ACC0 in w
>> clrc
>> rlf   ACC0,f
>> rlf   ACC1,f
>> rlf   ACC0,f
>> rlf   ACC1,f
>> rlf   ACC0,f
>> rlf   ACC1,f  ; ACC1:ACC0 =3D 8 * input
>> addwf ACC1,f  ; C + ACC1:ACC0 =3D 264 * input
>> rrf   ACC1,f
>> rrf   ACC0,f  ; ACC1:ACC0 =3D 132 * input
>>

Not wishing to steal any thunder from Mike's great bit of code but I=20
thought I'd mention that with a tiny extension this can be made to=20
multiply by 133

addwf	ACC0,f	; ACC0 =3D 133 * input
btfsc	STATUS,C
incf	ACC1,f	; ACC1:ACC0 =3D 133 * input

Regards
Sergio
--=20
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