In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Tristonaz wrote:

Hello,

I'm in a microcontroller class and my instructor has agreed to let me use the SX instead of the pic kits here. For my first project i am supposed to modify the ADC program on page 302 of "Programming the SX Microcontroller". The idea is to modify it so that instead of controlling the PWM , port B will be used to output an eight bit binary number to some LED's. The binary number will be higher for greater voltages and smaller for lower voltages. Now I've been playing around with this program for awhile now and no matter what i do I can't get the LED's to reflect the voltage at the output. The Code is commented below, so It should be relatively easy to follow (I hope). i believe it to be a logical error, but I'm still really new to the sx assembly language.

I thank you for any help you can give me.

Triston


*********************Code******************************
include "Setup28.inc"
Reset	main

TRIS	equ $0f
LVL	equ $0d
PWMpin	equ rb.6	;Port pin for PWM output

IntPer	equ 163

org	$08
PWMAcc	ds 1		;Counter for PWM

org	50h		;Bank 2 variables
analog	  equ $		;ADC bank
port_buff  ds 1
adc0	   ds 1		;ADC0 Value
adc0_acc   ds 1		;ADC0 Accumulator gb
adc0_count ds 1		;Time Counter

org	$000
bank	analog		;select ADC bank

;**Virtual peripheal for two A/D Converters *************************
;
adc
 mov	w, >>rc		;Read Current state of ADC's
 not	w		;turn inputs to outputs
 and	port_buff,w	;Save new value in buffer
 mov	rc,port_buff	;Refresh charge Discharge lines

 sb	port_buff.4	;ADC0 above threshold ?
  incsz adc0_acc	;if so, increment accumulator
 inc	adc0_acc	; and avoid overflow by skipping
 dec	adc0_acc	; the second inc instruction



 inc	adc0_count	; increment the counter
 jnz	:done_adcs	; Continue if not yet done
 mov	adc0, adc0_acc	;Update ADC0 value
 clr	adc0_acc	;Clear ADC0 accumulator

:done_adcs


 
 mov	w, #-IntPer	; Call ISR every 'IntPer' cycles
 retiw	

org 	$100
;** The Main program ***********************************************
main
 clr	rc		;intialize Port C
 mov	!rc, #%10101111 ;Configure Port C I/O pins
 mov	!rb, #%00000000 ;Configure Port B output for LED
 mode	LVL		;Set port C input to CMOS
 mov	!rc,#0		; CMOS
 mode	TRIS		;Restore MODE direction

include "Clr2x.inc"	;Clear all data memory

 mov	!option,#%10011111 ;Enable RTCC interrupt
 
:loop
 bank	analog
 mov	w,adc0
 mov	rb,w
 jmp :loop

---------- End of Message ----------


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