Abstract: In a compression mode in which plaintext data is input, and compressed, a first code that is an error detection code is generated with respect to the plaintext data, and compressed. A circuit generates restored plaintext data in which the compressed data is decompressed, for confirming successfulness. A second code that is an error detection code is generated with respect to the restored plaintext data and is compared with the first code. In a case where the first code and the second code agree, the compressed data and the first or second code are output. In a decompression mode, plaintext data is generated in which the input compressed data is decompressed. A third code that is an error detection code is generated with respect to the plaintext data and is compared with an input code, and when the input code and the third code agree, the plaintext data is output.

Abstract: A rubber endless track belt assembly for use in a crawler type track mechanism, which has a rubber endless track belt and a plurality of metal cores embedded at an equal spaced distance to one another in the belt along the longitudinal direction thereof. Each of the metal cores is provided with a pair of intermediate guide lugs spaced apart from each other and projecting outwardly on the inner peripheral side of the belt, a pair of wing portions each projecting horizontally in the transverse direction of the belt and embedded therein, and a pair of flat surface zones to which bogie wheels are thrustedly and rotatingly contacted, each of which zones being formed between the guide lug and the wing portion so as to extend in the longitudinal direction of the belt over the width of the wing portion and to be exposed on the inner peripheral side of the belt.