Instructions Circuit Diagram

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After the transmission of a program the microcontroller stops execu-
ting the bootloader and starts the execution of the received and newly
stored program.
The bootloader occupies a permanent and protected area in the
normal microcontroller ‘Flash’-memory and cannot be altered or de-
leted without special tools. The area is protected against erasure and
modicationsandyouwillfeelsafeatprogrammingthesystem.
Developing programs
How do I start developing a program?
In fact we will use the following method:
You will ‘write’ a YETI-program in a text editor, using a special ‘langu-
age’.Havingcompletedthetextleyouwilltranslatethetextleto
anotherlecontaininginstructions,whichmaybeunderstoodbythe
microcontrollersystemandiscalleda‘hex’-le.Andnallywewilluse
thepreviouslydescribed‘Flash’-programtotransferthe‘hex’-letothe
YETI.
We might even consider writing a program for the microcontroller by
editing ‘hex’-instructions! Although you may succesfully complete small
programs, you will soon consider this method being too complicated
and return to the standard programming method.