Re: [avr-gcc-list] Problem reading from EEPROM

[Arthur Goldhammer]

----- Original Message ----- 
From: "Jack Valmadre" <address@hidden>
To: <address@hidden>
Sent: Monday, July 14, 2003 5:31 PM
Subject: Re: [avr-gcc-list] Problem reading from EEPROM


> I am thinking of using EEPROM variables later in my program, if you could
> tell me how you prevented the EEPROM erasing when you loaded the program
on
> to the chip, that'd be a great help so that I don't run into any problems
in
> the near future (I'm kinda pressed for time).
> Thanks,
> Jack
>

Hi, Jack
I'm using an STK200 with uisp. I have the following lines in my Makefile:

PROGRAMMER = /usr/local/bin/uisp
PROGFLAGS = -dprog=stk200
....
install: $(PRG).srec
 $(PROGRAMMER) $(PROGFLAGS) --erase
 $(PROGRAMMER) $(PROGFLAGS) --upload if=$<
 $(PROGRAMMER) $(PROGFLAGS) --verify if=$<
 $(PROGRAMMER) $(PROGFLAGS) --segment=eeprom --upload if=$(PRG)_eeprom.srec
 $(PROGRAMMER) $(PROGFLAGS) --segment=eeprom --verify if=$(PRG)_eeprom.srec

This loads both the program and the EEPROM, where the data for the latter
are distinguished by the _eeprom suffix, produced as follows in the
Makefile:

%_eeprom.srec: %.elf
 $(OBJCOPY) -j .eeprom --change-section-lma .eeprom=0 -O srec $< $@

I am not able to get uisp to load the program code and EEPROM independently.
Even if I use --segment=flash on the --erase, the EEPROM seems to get
erased. Using the AVR loader on Windows, I was able to load flash and EEPROM
separately. I'm not sure why I can't get it to work with uisp. If anybody
can tell me, I'd be grateful. In the meantime I've got the program working
by this brute force method.

Art