FabiaTech Corporation77¾ DMA Channel MapThe equivalent of two 8237A DMA controllers is implemented in the FB2631 board.Each controller is a four-channel DMA device that will generate the memoryaddresses and control signals necessary to transfer information directly between aperipheral device and memory. This allows high speeding information transfer with lessCPU intervention. The two DMA controllers are internally cascaded to provide fourDMA channels for transfers to 8-bit peripherals (DMA1) and three channels fortransfers to 16-bit peripherals (DMA2). DMA2 channel 0 provides the cascadeinterconnection between the two DMA devices, thereby maintaining IBM PC/ATcompatibility.The following is the system information of DMA channels:DMA Controller 1 DMA Controller 2Channel 0: Spare Channel 4: Cascade forcontroller 1Channel 1: Spare Channel 5: SpareChannel 2: Spare Channel 6: SpareChannel 3: Spare Channel 7: Spare
