Data storing system for a communication control circuit

摘要

The data storing system according to the present invention is used for a communication control circuit. The communication control circuit is equipped with a communication sequencer, which takes in a message to be transmitted to a multiplex bus, an ID table which registers data IDs of messages necessary for the station, and the first and second memory circuits which have memory areas keyed to the data IDs. When the communication sequencer takes in a message, it determines whether its data ID exists in the ID table. If the data ID exists and the frequency of occurrence is high, then data following the data ID is temporarily stored in a memory area keyed to a data ID of the first memory circuit. If the data ID exists and the frequency of occurrence is low, then the data following the data ID is temporarily stored in a memory area of the second memory circuit. When a CPU reads the aforementioned stored data, it sets the status area of the storage area, in which the data was stored, for a state that enables a data storage change.