FabiaTech FX5634 Fanless Series, User Manual

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FabiaTech Corporation
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DMA Channel Map
The equivalents of two 8237A DMA controllers are implemented in the FX5634
board. Each controller is a four-channel DMA device that will generate the
memory addresses and control signals necessary to transfer information directly
between a peripheral device and memory. This allows high speeding information
transfer with less CPU intervention. The two DMA controllers are internally
cascaded to provide four DMA channels for transfers to 8-bit peripherals (DMA1)
and three channels for transfers to 16-bit peripherals (DMA2). DMA2 channel 0
provides the cascade interconnection between the two DMA devices, thereby
maintaining IBM PC/AT compatibility.
The following is the system information of DMA channels:
DMA Controller 1 DMA Controller 2
Channel 0: Spare Channel 4: Cascade for
controller 1
Channel 1: Reserved for
IBM SDLC Channel 5: Spare
Channel 2: Diskette
adapter
Channel 6: Spare
Channel 3: Spare Channel 7: Spare