Documented the usage of the internal oscilator

README.md

@@ -11,15 +11,25 @@ Programmer, e.g.:
 * AVRISPmkii
 
 ## Software
+### Arduino
+
 In order to flash the software, select the following settings in Arduino:
 * Tools | Board "Arduino NG or older"
 * Tools | Processor "Atmega8"
 
+In your arduino installtion, update the CPU frequency, as we are using the internal clock with 8Mhz.
+Find the following file */hardware/arduino/avr/boards.txt*.
+Inside the file, search for the chapter **Arduino NG or older w/ ATmega8** and add the following line:
+```
+atmegang.menu.cpu.atmega8.build.f_cpu=8000000L
+```
+
+### Avrdude
 The flashing itself is done with **avrdude**:
 ```bash
 avrdude -c AVRISPmkii -p m8 -u -U flash:w:SideboardLED.ino.standard.hex
 ```
 Initial once the fuses must be burned:
 ```bash
-avrdude -c avrispmkii -p atmega8 -U lfuse:w:0xee:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m
+avrdude -c avrispmkii -p atmega8 -U lfuse:w:0xe4:m -U hfuse:w:0xd9:m -U efuse:w:0xfc:m
 ```