Digi NS9750 - Manual (Page 533)

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B B u s D M A C o n t r o l l e r
DMA channel assignments
Each BBus DMA controller contains 16 DMA channels. Controller DMA1 is dedicated to
the BBus peripherals. Controller DMA2 is dedicated to the USB device endpoints. Any
given DMA channel is hard-wired to a peripheral.
Table 310 indicates which peripherals are hard-wired to which DMA channels, and the
DMA mode (direction) required for each. These are the DMA modes:
FBR — Fly-by memory-to-peripheral
FBW — Fly-by peripheral-to-memory
FBRW — Fly-by programmable for either direction
DMA Channel DMA channel peripheral Fly-by direction
DMA1 1 SER channel B receiver FBW
DMA1 2 SER channel B transmitter FBR
DMA1 3 SER channel A receiver FBW
DMA1 4 SER channel Atransmitter FBR
DMA1 5 SER channel C receiver FBW
DMA1 6 SER channel C transmitter FBR
DMA1 7 SER channel D receiver FBW
DMA1 8 SER channel D transmitter FBR
DMA1 9 1284 command receiver FBW
DMA1 10 Unused N/A
DMA1 11 1284 data receiver FBW
DMA1 12 1284 data transmitter FBR
DMA1 13 Unused N/A
DMA1 14 Unused N/A
DMA1 15 Unused N/A
DMA1 16 Unused N/A
Table 310: DMA channel assignments