10F222 Wake on pin change

[gadelhas]

Hi;

Here is a program that i wrote in the past.

'****************************************************************
'*  Name    : Temporizador 3m p/ Lavar Dentes.BAS               *
'*  Author  : gadelhas                                          *
'*  Notice  : Copyright (c) 2012 ProSystems                     *
'*          : All Rights Reserved                               *
'*  Date    : 01-03-2012                                        *
'*  Version : 1.0                                               *
'*  Notes   : Proteus + Circuito com SOT-23 e CR2032            *
'*          : 10F222 - Wake from sleep através de IOC no GP3    *
'****************************************************************
@ __config _IOFSCS_4MHZ & _WDT_OFF & _MCLRE_OFF & _CP_OFF & _MCPU_ON

 DEFINE OSC 4

 '===================SRF AND PINOUT CONFIGURATION - 1-In / 0-Out=================
              '76543210
     TRISIO = %00001000
       GPIO = %00000000
 OPTION_REG = %00000000 'OPTION_REG.7 - Wake on change bit 0=Enable
     ADCON0 = %00000000 'Analog pins disable

'==================================ALIAS========================================
 VAZIO1 VAR GPIO.0
 VAZIO2 VAR GPIO.1
 LED    VAR GPIO.2
 MCLR   vAR GPIO.3
 GPWUF  var STATUS.7
 
'=================================VARIABLES=====================================
 I VAR BYTE
 C VAR BYTE: C = 0
 
'================================MAIN LOOP======================================
@ movlw 0x01A  ;OSCCAL Value
@ movwf OSCCAL

 IF GPWUF = 0 THEN DESLIGA  'Test what caused the Reset
 
Main:

 WHILE MCLR = 0    'If button pressed for 3 seconds, turn on led
    PAUSE 100
    C = C + 1
    IF C = 30 THEN LIGA
 WEND
 
 FOR I = 0 TO 119 '~120 Segundos a Piscar de 1 em 1 Segundo
    HIGH LED
    PAUSE 500
    GOSUB VERIFICA 
    LOW LED
    PAUSE 500
    GOSUB VERIFICA
 NEXT

 FOR I = 0 TO 59  '~30 Segundos a Piscar de 0,5 em 0,5 Segundo
    HIGH LED
    PAUSE 250 
    LOW LED
    PAUSE 250
    GOSUB VERIFICA
 NEXT

 HIGH LED
 FOR I = 0 TO 59  '~30 Segundos sempre ligado
     PAUSE 500     
     GOSUB VERIFICA
 NEXT
 LOW LED
  
 'Sequencia de finalização
 HIGH LED: PAUSE 100: LOW LED: PAUSE 100
 HIGH LED: PAUSE 100: LOW LED: PAUSE 100
 HIGH LED: PAUSE 100: LOW LED: PAUSE 100

DESLIGA:
 C = 0
 I = GPIO     'Must read GPIO before entering sleep. Read the Datasheet
@ SLEEP
@ NOP
GOTO Main

'================================SUB-ROUTINES===================================
LIGA:
    HIGH LED
    PAUSE 1000
    WHILE MCLR !=0
    WEND
    LOW LED
GOTO DESLIGA

VERIFICA:
 IF MCLR = 0 THEN
     C = C + 1
     IF C = 6 THEN
         'Sequencia de finalização
         HIGH LED: PAUSE 100: LOW LED: PAUSE 100
         HIGH LED: PAUSE 100: LOW LED: PAUSE 100
         HIGH LED: PAUSE 100: LOW LED: PAUSE 100
         PAUSE 1000
         GOTO DESLIGA
     ENDIF        
 ENDIF
RETURN
END

[ruijc]

With that said I really wouldn't want to run it at anything above 5.5V......

I agree...But for that you can just add a diode in series to lower the voltage down a bit.

Regards
Rui

[AvionicsMaster1]

Good idea on the diode. Thanks.

I know what RTFDS says but for what I'm doing I assume the four AAA batteries are putting out somewhat less than 1.5V and typically the four pack is close to 5.6V. After a short period they are below the 5.5V level and stay like that for a long time with only a 3uA draw. They'll last even longer if I can get it down in the nano Amp range.

I've yet to try the ASM sleep but will try soon. Thanks for ideas.

[Charlie]

Brand new batteries will actually put out more than 1.5V. I'd recommend the diode. Also helps for the day you accidentally put them in backwards. Or use NiCDs.

[Demon]

Would a low drop off 7805 help?

Robert

[Charlie]

How low is low? They usually need over a volt. Can you point to a spec sheet?

[HenrikOlsson]

Hi,
I don't really see the point of linear regulator. A 5V one, LDO or normal, will drop out of regulation pretty quick, then it behaves as if it wasn't there in first place - or worse. Using a lower voltage like 3.3V or 2.5V will only turn useful energy into heat in the regulator so that's no good either.

The "best" way would of course be a switching type boost/buck converter/regulator so that the PIC can be fed 2.5V (or whatever) from "any" supply voltage, the good thing about this is that the PIC Draws much less current at lower supply voltages so provided the converter/regulator is efficient you'd get more use out of the batteries. But, it adds complexity so.....perhaps use 3 cells in series instead of 4.

/Henrik.

[Demon]

How low is low? They usually need over a volt. Can you point to a spec sheet?

I haven't used one yet. I checked a few and can't find one that comes even close to what is needed here.

They should call them NAMDO; Not As Much Drop Off instead of LDO.

Robert