Abstract: A communication processing system provided with one parent communication unit, at least one child communication unit, and at least one first detachable unit detachable from the at least one child unit, the system being operated in accordance with an operation program stored in a second detachable unit detachable from the parent unit, includes a transfer unit for transferring the operation program to the at least one child unit, a first storage unit for storing the operation program transferred from the parent unit by the transfer unit when the second detachable unit is mounted on the parent unit, the first storage unit being provided in the first detachable unit, and a second storage unit for storing a receiving program for receiving data sent from the parent unit, the second storage unit being provided in the first detachable unit. The first storage unit is provided in the first detachable unit. The second storage unit is provided in the first detachable unit.

Abstract: Pulse wave modulation waveform signals of three-phase alternating-current necessary for driving a compressor used in an air-conditioner incorporating an inverter circuit are, for example, generated by preliminarily storing the reference waveform data in a ROM, reading out sequentially, and executing specified data conversion instructions. In a signal generation circuit of the invention, a waveform generation circuit for execution of such data conversion is provided independently of a central processing unit (CPU), and after setting initial data from the CPU, the waveform data are directly read into the waveform generation circuit from the ROM by DMA transfer system to perform data conversion. That is, the CPU is not related with the data conversion, and therefore it is not necessary to create waveform data reading program and data conversion program.