System for transferring data through a communication interface using control information in request data for controlling data receiving rates independent of the CPU

摘要

A data processing apparatus which has a communication interface element for connecting between an external apparatus and outputting element. The outputting element outputs the data received from the external apparatus by a normal speed parallel communication through the communication interface element. The data processing apparatus includes a DMAC for connecting between the communication interface element and the outputting element. Designating data which can be included in the received data designates performing a high speed parallel communication. The DMAC is started in response to the designating.