User guide

SmartBook for Renesas R8C/Tiny Microcontrollers

www.MightyMicons.com

The facility to define the required instructions in different formats seems like a

surprise to many designers. Many designers may also take the whole thing as a

kind of waste of the device resources. But, R8C/Tiny designers have done lots of

home work to create a way enabling the designers to finish their applications in

their target memory size with the required speed and performance.

In general, the designers need not worry about the type of the format for their

application code. Even though there is a space to define the instruction format in

the definition of the instructions, designers can happily ignore this part. The

software tools like Assemblers and the C Compilers take care of the optimum

format for the instructions to suit many applications. Suppose, if you ask the

compiler to work out your application code within the target memory size, you

can be sure that the compiler finishes the job meeting your requirements. Similarly,

when you need more performance from the device, when using compiler, you are

assured of the application code that could make you happy at the end of the

compilation.

In short, R8C/Tiny devices generate the required application code meeting your

exact needs by exploiting the redundancy built in the instruction set.



 The

quick format

takes about two to four

instruction bytes.

 

Short

format contains an opcode in a

single byte and zero to two source

bytes along with

zero to two destina-

tion bytes.

 

Zero for-

mat has one single byte

opcode and zero to two

destination bytes.