Hz converter to Frqa in Asembler for beginners

hal2000

HZ converter to Frqa in Asembler
Hi, I think that this routine can be useful.
You may already published another user's·
In routines where you have to be doing many frequency adjustments
is slow spin, that is why I translated it to Assembler
Forgive my bad English ;-)
The code has commentary in Spanish.
It is code to be added to your routine in Assembler

Greetings to all

Code Assembler:

DAT

'Ejemplo de uso

' mov hz,y·············· 'HZ envia

' call #Com_fre········ 'llama a la rutina

' mov frqa,F_os······· 'F_os tiene el valor para el oscilador

'

'==========================================================================

'Covierte HZ en NCO el regitro de entrada es Hz y el d salida F_os

'==========================================================================

Com_fre··········· mov···F_os,#0

······················ shl···· Hz,#1

······················ mov·· rep32,#32

Fre_loop··········· shl···· F_os,#1

······················ cmps· CLKFRE,Hz wc,wz

········· if_c_or_z subs· Hz,CLKFRE

········· if_c_or_z adds· F_os,#1

························ shl·· Hz,#1

······················ djnz·· rep32,#Fre_loop

Com_fre_ret ret

CLKFRE long 80_000_000

HZ res 1······························· 'variables conversor de frecuencia al oscilador

F_os res 1

rep32 res 1



Code SPIN

PRI HzToNCO(a) : f

a <<= 1

repeat 32 'perform long division of a/clkfreq

f <<= 1

if a => CLKFREQ

a -= CLKFREQ

f++

a <<= 1



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Did the curiosity kill the cat?
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Envio editado por (hal2000) : 9/26/2009 2:28:26 PM GMT