Fuses issue on 16f884.... Locked out ??

[andybarrett1]

Hi Wonder if anyone can help.... I have locked myself out of 3 x 16f884's I think with fuses in the configuration ??

I am using MPASM.... The fuse details look like this:-

;****************************************************************
;*  16F884.INC                                                  *
;*                                                              *
;*  By        : Leonard Zerman, Jeff Schmoyer                   *
;*  Notice    : Copyright (c) 2009 microEngineering Labs, Inc.  *
;*              All Rights Reserved                             *
;*  Date      : 07/02/09                                        *
;*  Version   : 2.60                                            *
;*  Notes     :                                                 *
;****************************************************************
        NOLIST
    ifdef PM_USED
        LIST
        include 'M16F88x.INC'	; PM header
        device  pic16F884, intrc_osc_noclkout, wdt_on, mclr_on, lvp_off, protect_off
        XALL
        NOLIST
    else
        LIST
        LIST p = 16F884, r = dec, w = -302
        INCLUDE "P16F884.INC"	; MPASM  Header
        __config _CONFIG1, _INTRC_OSC_NOCLKOUT & _WDT_ON & _MCLRE_OFF & _LVP_OFF & _CP_OFF
	__config _CONFIG2, _WRT_OFF
        NOLIST
    endif
        LIST

When I go to reprogram I get :-

Device is data protected! Data memory may be invalid.

Device is code protected! Program memory may be invalid.

Can anybody help ?? Can I clear the protection so I dont loose the chips :-)

Thank you for reading

BR
Andy

[HenrikOlsson]

Code protection does not (should not) prevent the device from being erased and when it's erased the code protection bits are erased. Besides, your config says CP_OFF so I would THINK the device is NOT actually code protected.

I see you're using internal oscillator and you have MCLR off, I wonder if this may be related to the issue in the other thread with the bricked 12F675 part.
Do you need to have MCLR off or can you possibly try another PIC with MCLR on and see if that makes it better?

What programmer are you using?

/Henrik.

[andybarrett1]

Hi Thank you for reply....

I can turn MCLR on see if makes a difference later .....
But does mean sacrificing an other chip... Got through 5 so far :-)

programmer is a PicKit 2 I think... Not in office at moment ... It is the default one in MPLAB ?

BR
Andy

[andybarrett1]

Hi Henrik

Programmer is a "Picstart Plus"...... But also does exactly same thing with a "Dataman 48-Pro"

Then turned the MCLR on in the config....programmed up my last 884.... changed some code..... programmed again and now working.

You are a star..... Thank you. Easy for me to change h/w to put a little RC on the reset

But why is this a problem ?????

Thank you again

Andy

[HenrikOlsson]

Wow, PICStartPlus, there's a blast from the past, haven't used mine for probably 10 years.

Did you read the other thread I linked to?
The problem occurs when you're using internal MCLR AND internal oscillator. But there's plenty to read on the subject so I won't go into details here.

If you can use external MCLR that's the easiest way to get around the problem, it's not recommended to use R/C network on the MCLR pin, a simple pullup is enough in 99% of the cases.

/Henrik.

[andybarrett1]

Well thank you Henrik

Yes I have just had a look see at the link .......Have saved it for reference .

Not sure if I can get my 6chips back though.....Be. Good as land fill !!

Thank you again

Andy

[Demon]

Andy, I keep all my old ICs and components in a jar. When I have enough, I put them in a plastic container (margarine or whatever from recycling bin), and throw in any scrap circuits then take everything to local recycling center. Whenever I get a new dude on the job, I just tell them to process these with televisions and computers.

They can get a surprising amount of gold and other metals back from these garbage parts now.

Robert

[andybarrett1]

I may just try that :-)

BR
Andy