[PIC] High Power Consumption for a Battery operated application - Electronic Safe

Hi,

 

I need help with the power consumption on a battery operated project (Keypad
safe)

I have a lot of safes and the controllers is damaged. I want to create new
controllers for these safes and try to use what is available

 

Details: Current Power is supplied by 4xAA Batteries. Power is dropped to
4.8 volt through 2 diodes.

 

I used PICBASIC Pro and the software works perfect except the current draw
is about 1.56mA. The datasheet show on page 167 a current draw of 1uA in
sleep mode. I use the PIC16F88. That is with the programmer disconnected.( I
measure about 156,8mV volt drop over a 100Ohm resistor )

 

What am I missing or doing wrong? 

 

The Software in short:

 

Config:

    __config _CONFIG1, _INTRC_CLKOUT & _WDT_OFF & _LVP_OFF & _CP_OFF &
_BOREN_OFF & _MCLRE_ON & _DEBUG_OFF 

    __config _CONFIG2, _FCMEN_OFF & _IESO_OFF

 

Pin Setup: 

Row1 VAR PORTA.0                         '4x3 Keypad 

Row2 VAR PORTA.1

Row3 VAR PORTA.2

Row4 VAR PORTA.3

 

Col1 VAR PORTB.0

Col2 VAR PORTB.4

Col3 VAR PORTB.5

 

' Other pins

    Solenoid VAR PORTA.4         ' Solenoid control pin

    Beeper VAR PORTB.3           ' Beeper control pin

    ResetButton VAR PORTB.6      ' Reset button

    Led var PORTB.2              ' heartbeat

 

Initialize:

    OSCCON = %01101110               'set int rc osc to 4mhz

 

      CMCON = 7              ' Disable comparators, PORTA as digital I/O

      ANSEL = 0              ' Set all pins as digital I/O

      ADCON0 = 0             ' a to d off

      ADCON1 = 0              '??

      T1CON = 0

      T2CON = 0              ' timer 2 off

      CCP1CON = 0            ' capture compare off

      TXSTA = %00000000      '??

      RCSTA = %00000000      '??

      

      PORTA = 0              ' Initialize PORTA to 0

      PORTB = 0              ' Initialize PORTB to 0

      

      TRISA = %00000000       ' Set PORTA direction (input/output as needed)

                              ' RA0 - RA3 keypad row - outputs

                              ' RA4 - stryker - output

                              ' RA5 - reset mclr - set as input

                              ' RA6 - RA7 osc

      TRISB = %01110001       ' Set PORTB direction

                              ' RB0 - col1

                              ' RB1 - nc   

                              ' RB2 - LED   

                              ' RB3 - Buzzer

                              ' RB4 - Col2

                              ' RB5 - Col3

                              ' RB6 - nc Programmer

                              ' RB7 - nc Programmer 

                                  

      

      OPTION_REG.7 = 0           ' Enable weak pull-ups on PORTB

      OPTION_REG.6 = 0           ' TRIGGER INT ON FALLING EDGE

 

I then enable interrupt :

INTCON = %10011000                            ' enable change on port[B4-B7]
and ext int on port b

                                                            

ON INTERRUPT GOTO Handleinterrupt             ' Interrupt Service Routine

 

Main Routine:

 

Check for KeypressedFlag

Check for ResetPressedFlag

 

Flash LED 

 

Goto Sleep:

 

OSCCON = %00000010    '32KHz

            

            asm

            sleep

            endasm

 

             OSCCON = %01101110    '4MHz

 

.and goto Main

 

Here is my Interrupt Handler.

Disable

HandleInterrupt:

    if resetbutton = 1 then

        ResetPressedFlag = 1

        resume

    endif    

      

    IF INTCON.1 = 1 THEN        ' Check external INT (RB0)

        KeyPressedFlag = 1      ' Set flag for RB0

        INTCON.1 = 0            ' Clear external INT flag

    ENDIF

    

    IF INTCON.0 = 1 THEN        ' Check IOC interrupt

        'IF (PORTB & %00110000) <> %00110000 THEN

            KeyPressedFlag = 1  ' Set flag if RB4 or RB5 changes

        'ENDIF

        INTCON.0 = 0            ' Clear IOC flag

    ENDIF

    

    RESUME

    enable

 

I am currently using the PIC16F88. I tried to drop the voltage below 4Volt
with disastrous effects.

 

Should I get another PIC? . I don't want to replace the batteries every
month.

 

Regards

 

Francois