topic Re: Unable to erase the flash on a GT16A in 8-bit Microcontrollers

Unable to erase the flash on a GT16A

Hawkeye — Sat, 12 Dec 2009 05:30:29 GMT

I can not erase the flash when using PROGHCS08 v1.40. Typically it re-initializes when I choose to erase the module.

The problem is with our board which we have modified. With the old board I have no problems but with the new one it fails. The changes on the board are not supposed to impact the MCU but obviously they do.

One difference I see when attempting erase the flash is that with our new board and v1.04 of the algorithm the programmer reports a bus frequency of 7741 KHz. With an older version of the algorithm it was reporting a bus frequency of 3685 KHz. With a working board the bus frequency is reported as 15546 KHz.

Can anybody suggest why the frequency is different or what to look at to solve this problem?

Thanks

Re: Unable to erase the flash on a GT16A

peg — Sat, 12 Dec 2009 06:10:31 GMT

Hello Hawkeye,

Are you saying you can connect to the device with out any problem but only get a problem with the erase command?

Are you securing the device previously?

I use the GT16A a lot and have not seen any problem like this.

Re: Unable to erase the flash on a GT16A

Hawkeye — Mon, 14 Dec 2009 23:03:07 GMT

Thanks for the response Peg.

Yes I can connect to the device (and read the System Device ID registers) but can not erase or program the device.

It is a new device and the programmer software reports that it is unsecured.

Both the programmer and debugger read NVOPT as $FE.

The programmer reads FOPT as $C2.

There are 4 bytes which are not erased:

$FFBE = $73

$FFBF = $FE

$FFFE = $00

$FFFF = $80

The difference I have seen between the the two boards is the bus frequency reported by the programmer.

We use the GT16A on the old board and do not have this problem. There is something different with this board or maybe this individual device is damaged. I am trying to get the device swapped but I think the tool is not working.

Thanks

Re: Unable to erase the flash on a GT16A

Hawkeye — Tue, 15 Dec 2009 03:23:05 GMT

Maybe I am not really "connected" to the GT16A as the programmer always initializes and loads the programming algorithm when I select Erase Module.

Can anybody tell me why it would do that?

Thanks

Re: Unable to erase the flash on a GT16A

Hawkeye — Thu, 24 Dec 2009 22:14:40 GMT

Replacing the mcu solved the problem.