By integrating the DMA and I/O function the number of required bus cycle can be reduced. In this configuration, the DMA module and one or more I/O modules are integrated together in such a way that the system bus is not involved. In this case DMA logic may actually be a part of an I/O module, or it may be a separate module that controls one or more I/O modules.

The DMA module, processor and the memory module are connected through the system bus. In this configuration each transfer will use the system bus only once and so the processor is suspended only once.

The system bus is not involved when transferring data between DMA and I/O device, so processor is not suspended. Processor is suspended when data is transferred between DMA and memory.
The configuration is shown in the Figure 6.12.
                           

                            Figure 6.12: Single bus integrated DMA transfer