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Microcontroller Programming » Foodloader help

June 04, 2010
by n3ueaEMTP
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I picked up some 328's from mouser & want to install the NK bootlaoder. I've looked around the fourms to make sure I did it correctly but I am questioning my work. Foodloader loaded OK but the last line was:

avrdude: 31756 bytes of flash verified

Something tells me I've made a mistake somewhere but all I did was change the -c dapa to my programmer (usbtiny). Is this correct or do i need to do more work to get the NK bootlaoder correctly loaded?

Thanks Chris B.

June 06, 2010
by mrobbins
(NerdKits Staff)

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Hi Chris,

That sounds right. When I look in bootloader328P at the foodloader.hex file, avr-size reports 1036 bytes in length. This gets installed in the last 2kB of the ATmega328P's flash memory space, so the final position is at memory location:

32*1024 - 2*1024 + 1036 = 31756

The avrdude output might be confusing because it's actually reporting the final memory position written instead of the total number of memory positions written, but it's fine!

Mike

June 06, 2010
by n3ueaEMTP
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OK, thanks Mike. I was thinking that is how much bytes the program used. Now I know for next time. Thanks again!!

June 11, 2010
by n3ueaEMTP
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New question. I've downloaded a program that reads the time from a DS1307 RTC and communicates with the MCU via the TWI (I2C) module. In the opening comments of the program, there is this note:

ATmega8 Running at 1MHz Internal Clock. Fuse Byte set as |follows. | |LOW=0x21 HIGH=0xD9

I'm using the AVR Pocket Programmer from Sparkfun. I tried modifing the bootloader makefile but that didn't go so well. Can anybody point me in the right direction please?

Chris B. n3ueaEMTP

June 11, 2010
by n3ueaEMTP
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I forgot to ask the question, how can I change the fuses to match what the program needs?

Sorry about that.

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