DMA Units
A MultiCam channel needs one digitizing unit to transfer the camera video data into an single well-organized array of the frame buffer area.
The rationale for a PC based frame grabber is to transfer the camera picture into the PC memory. To efficiently achieve this goal, the Domino Melody board incorporates one DMA machine able to transport the frame buffer data into the PC memory surface.
DMA means "Direct Memory Access". This means that the data transfer is done through the PCI bus without intervention of the PC CPU.
The following block diagram helps to visualize the concept.
DMA units