Communication control system for transmitting, from one data processing device to another, data of different formats along with an identification of the format and its corresponding DMA controller

摘要

In communication control devices having a DMA transfer function and communication control systems for performing a data transmission between such communication control devices, it is desired to reduce time required for processing. In accordance with the present invention, a transmitted data is written in a receiving side memory by a write instruction from the transmitting side CPU. Alternatively, DMA controllers and receiver side memories are changed from one to another in response to a format representing the transmission information. Alternatively, write addresses in the receiver side memory are changed from one to another depending on the format of transmission information. Alternatively, DMA transfer to a buffer memory is controlled by an address counter. In such a manner, a procedure for transfer of data can be simplified.