The micro controller has a number of fuse and lock bits. These have to be set/programmed before you can use the micro controller in the PCB. With eXtreme burner you can easily program the fuse bits.

Values we need:

- Lockbyte: : protect the Flash against reading/writing. If you set these bits, you can not read/write the micro controller anymore.   So, be careful and be sure if you do this.                                               
- Fusebyte lo: Startup-time, Clk-Source = Crystal/Quarz
- Fusebyte hi: serial program, preserve EEPROM, Osz-Amplitude, Bootsize
- Fusebyte ex: brown out = 4,3 V

Here are the values in bit and hex format:

$PROG &b11111111  (&hFF) , &b10011110 (&h9E) , &b11010001 (&hD1) , &b11111100 (&hFC)

 

Be careful with writing the Lockbyte. If you do this, eXtreme burner can not read any of the content anymore. Basically the chip is hardware from now on. Changing the content is not possible. You need a new chip,............5 euro's,.....

I notices this the hard way. I incidentally programmed the Lockbyte and while trying to do do anything, reading, writing, erasing,...gave me a "Power on FAIL" in eXtremeBurner.

 

So, we have now the fusebits and the firmware done. Last action is the boot loader.

 

 

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