Structured programming

clip_image002It is well known that any algorithm can be reformulated such that only very few control structures are needed. Structured programming and the well known Nassi-Shneidermann diagrams provides a solution to this problem. One can then use this structure to create algorithms made of components with very simple sequential flow of control: simply take each sub-block of the while-do-loops or if-then-else-conditions as a separate program residing in a different micro-controller.

The if-then-else construct and the while-do-loop are now transformed into special subroutine calls:

call_if == 0 free_working_area copy_working_area

call_while > w_start_addr work_loop.

These instructions mean:

• call the subroutine  free_working_area (which is a micro-controller with the correponding name) only executing this block as its program if the zero-flag of the accumulator is set. Otherwise, call the subroutine  copy_working_area (another micro-controller with that name and only the program-code of this 'else'-block).

• correspondingly, the while-do-loop is executed as long as the value in the accumulator is larger than the value in the register  w_start_addr, calling the micro-controller  work_loop.

Addressing of the different micro-controllers (i.e. their respective names) in biochemistry boils down to attachment of molecules. This attachment-procedure must of course be realized by a mechanism such as lock and key recognition because a global address-space is not available. It is reasonable that the specificity of this recognition procedure varies in the system and depends on the specific properties of the interacting molecules.

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