Hi, thanks for the advice, i have set it up to use 4 AAA batteries but it
does pretty much the same as the potential divider (wondering what the
difference is) however on closer inspection of the ticking comming from the
servo, the shaft is actually moving albeit very slow and weak (like a
ticking clock) so i am beginning to suspect that my timing pulses must be
off? here is some of my code:

;==========================================================================
;       Variable Definition
;==========================================================================
TIMER1		EQU	H'20'		;Used in delay routine
TIMER2		EQU	H'21'		; "	"	"	
TIMER3		EQU	H'22'		; "	"	" 

		ORG	0		;Reset vector address
		GOTO	RESET		;goto RESET routine when boot.


;		*********************************************
;		*  Example of a delay routine               *
;		*********************************************

DELAY_ROUTINE   MOVLW   D'38'         ;54 Generate approx 1.5mS delay at
4Mhz CLK
                MOVWF   TIMER2
DELAY_ROUTIN    MOVLW   D'255'         ;54 Generate approx 10mS delay at
4Mhz CLK
                MOVWF   TIMER3
DEL_LOOP1       MOVLW   D'255'	       ;60	
                MOVWF   TIMER1
DEL_LOOP2       DECFSZ  TIMER1,F
                GOTO    DEL_LOOP2
                DECFSZ  TIMER2,F
                GOTO    DEL_LOOP1
		RETLW   0


;	       **********************************
;              **  RESET :  main boot routine  **
;              **********************************

RESET		MOVLW	B'00000111'	;Disable Comparator module's
		MOVWF	CMCON
		;
		BSF	STATUS,RP0	;Switch to register bank 1
					;Disable pull-ups
					;INT on rising edge
					;TMR0 to CLKOUT
					;TMR0 Incr low2high trans.
					;Prescaler assign to Timer0
					;Prescaler rate is 1:256
		MOVLW	B'11010111'	;Set PIC options (See datasheet).
		MOVWF	OPTION_REG	;Write the OPTION register.
		;
		CLRF	INTCON		;Disable interrupts
		MOVLW	B'11000000'
		MOVWF	TRISB		;RB7 & RB6 are inputs.
					;RB5...RB0 are outputs.
		MOVLW	B'11111111'	;all RA ports are inputs
		MOVWF	TRISA
		BCF	STATUS,RP0	;Switch Back to reg. Bank 0
		CLRF	PORTB		
		;

EFFECT_1	MOVLW	B'00001100'	;Activate LD4 (RB3) & Send the pulse to servo on
LD3
		MOVWF	PORTB
		CALL	DELAY_ROUTINE
		MOVLW	B'00000000'	;Deactivate LD4 (RB3) & Servo
		MOVWF	PORTB
		CALL	DELAY_ROUTIN	;Small period delay
		GOTO	EFFECT_1
		END

this is basically an example LED flash code i modified and judging from the
original comments 255 = 10ms pulse so 38 should give around 1.5ms, maybe i
have miscalculated something or overlooked some detail, as i said this might
be easier if i could simulate and see the timing pulses myself but that
doesnt seem possible with some of the linux software i have tried so far

Jason


Jinx wrote:
> 
> Hi Jason, could you use 3 or 4 AAs instead of a 9V (I guess
> this is a PP3 type ?). Or is there a weight problem ? Maybe
> AAA or AAAA ?
> 
> Losing almost 1/2 a 9V battery's voltage in a linear regulator like
> the 7805 is very wasteful, and PP3s don't have a lot of capacity
> to start with. A better linear choice that's common would be the
> LP2950-5.0, and there are other low quiescent current ones. One
> of the big drawbacks with a 7805 is that it consumes 8mA just
> on its own. That's acceptable for a big battery or mains supply
> but not for smaller batteries. Low quiescent current regulators
> use only a fraction of the 7805, usually under 100uA (that's just
> an 80th or better of 8mA)
> 
> The above probably won't solve your motor problem but it's
> really worth thinking about
> 
> -- 
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
> 
> 

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