Relaton between Software Clock and Fuse bit

pinkfloyd11 · Joined: 02 Jul 2007 Posts: 247

Dear Friends

I have written a program that write on RS232 on ATMega8515 placed directly on STK500 Board.

I use software clock (XTAL1 jumper close; OSCSEL jumper close on 1-2)
set by AVR Studio board tab on 3.686 MHz

Now which fuse bit I should use on ATMega8515 for have RS232 communication work good (because I read strange word on rs232 an I know that this is clock error...)

If max software freq. is 3.686MHz why in list there are also 6 MHz, 8 MHz ecc and which is the difference between Int. Clcok, Ext Clock, Int osc ecc??

Thanks

Luciano · Joined: 29 Nov 2004 Posts: 3149 Location: Italy

Hi Giuseppe,

Read the ATmega8515 datasheet from page 34 to page 40.

ATmega8515 datasheet:
http://www.atmel.com/dyn/resources/prod_documents/doc2512.pdf

Best regards,

Luciano