Renesas 70 Manual De Usuario

   

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In line with recent rapid technological advances in microcomputers, the functions of microcomputer-based 
products have become complicated. In addition, the microcomputer program size has increased. Further, as 
product development competition has been intensified, manufacturers are compelled to develop their micro-
computer-based products within a short period of time. 

In other words, engineers engaged in microcomputer software development are now required to develop lar-
ger-size programs within a shorter period of time. To meet such stringent requirements, it is necessary to take 
the following considerations into account. 

One way to provide for software recyclability is to divide software into a number of functional modules 
wherever possible. This may be accomplished by accumulating a number of general-purpose subrou-
tines and other program segments and using them for program development. In this method, however, 
it is difficult to reuse programs that are dependent on time or timing. In reality, the greater part of ap-
plication programs are dependent on time or timing. Therefore, the above recycling method is applica-
ble to only a limited number of programs. 

There are various problems with team programming. One major problem is that debugging can be ini-
tiated only when all the software program segments created individually by team members are ready 
for debugging. It is essential that communication be properly maintained among the team members.   

One way to achieve this target would be to educate engineers to raise their level of skill. Another way 
would be to make use of a structured descriptive assembler, C-compiler, or the like with a view toward 
facilitating programming. It is also possible to enhance debugging efficiency by promoting modular 
software development. 

However, the conventional methods are not adequate for the purpose of solving the problems. Under these cir-
cumstances, it is necessary to introduce a new system named real-time OS 

To answer the above-mentioned demand, Renesas has developed a real-time operating system, tradenamed 
MR308, for use with the M16C/70, 80 and M32C/80 series of 16/32-bit microcomputers .   

When the MR308 is introduced, the following advantages are offered. 

When the real-time OS is introduced, timing signals are furnished via the real-time OS so that pro-
grams dependent on timing can be reused. Further, as programs are divided into modules called tasks, 
structured programming will be spontaneously provided. 

That is, recyclable programs are automatically prepared.   

When the real-time OS is put to use, programs are divided into functional modules called tasks. 
Therefore, engineers can be allocated to individual tasks so that all steps from development to debug-
ging can be conducted independently for each task.   

Further, the introduction of the real-time OS makes it easy to start debugging some already finished 
tasks even if the entire program is not completed yet. Since engineers can be allocated to individual 
tasks, work assignment is easy. 

As the use of the real-time OS makes it possible to divide programs into small independent modules 
called tasks, the greater part of program debugging can be initiated simply by observing the small 
modules.  

                                                      

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 OS:Operating System