AVR-EEPROM gets erased during programming

[Niro]

Dear all,

first of all: I used the forum search, and I already read the same topic concerning PIC...)

I have the same problem with an ATMega328P using FC4, but couldn't find a solution....
Could you please help?

Many Thanks,
Niro

[Spanish_dude]

I think this an option you need to add or remove when flashing, but I don't know more about it.

[Sean]

The option to save EEPROM data during a program download is controlled by the EESAVE fuse.

The default fuse settings recommended in the Flowcode documentation (Chip -> Configure menu) select the external crystal oscillator and cause all additional features to be disabled.:

0x0, 0xdf
0x1, 0xff


It is possible to use alternative settings (with reference to the manufacturer's device data sheets) to configure the device differently.
Note: Selecting a clock source that is not available to the device will stop chip operation and prevent it from being re-programmed in ISP mode.

There are several websites that provide AVR fuse value calculators

In the Flowcode configuration window, the first value in each pair is the fuse byte identifier, the second value is the fuse setting:

0x0 = Fuse High Byte
0x1 = Fuse Low Byte
0x2 = Fuse Extended Byte (if required)

Enabling EEPROM saving for the ATmega328P (with all other options set to recommended settings) requires the fuse settings:

0x0, 0xd7
0x1, 0xff

[Niro]

Thanks to all!

I actually found the most simple solution for me:

Start AVR Studio 4, conntect to the ATmega, then go to the Fuse Dialog and first READ the fuses, then set the EESAVE option and programm the fuse-settings.
Now Flowcode does the Flash-programming without erasing the EEprom.

Best Regards,
Niro