Rainbow Electronics DS3134 - Manual (Page 102)

DS3134
102 of 203
Receive DMA Memory Organization Figure 8.1.1B
Free Data Buffer Space
Receive Free Queue Descriptors:
Contains 32-Bit Addresses for Free Data
Buffers & their Associated
Free Packet Descriptors
Free Queue Base Address (32)
Free Queue End Address (16)
Free Queue Small Buffer Start Address (16)
Free Queue Large Buffer Host Write Pointer (16)
Free Queue Large Buffer DMA Read Pointer (16)
Free Queue Small Buffer DMA Read Pointer (16)
Free Queue Small Buffer Host Write Pointer (16)
Up to 64K Dual dwords
Free Queue Descriptors Allowed
Receive Done Queue Descriptors:
Contains Index Pointers to
Used Packet Descriptors
Done Queue Base Address (32)
Done Queue End Address (16)
Done Queue DMA Write Pointer (16)
Done Queue Host Read Pointer (16)
Up to 64K dwords Done Queue
Descriptors Allowed
Receive Packet Descriptors:
Contains 32-Bit Addresses
to Free Buffer as well as
Status/Control Information and
Links to Other Packet Descriptors
Descriptor Base Address (32)
Up to 64K Quad dwords
Descriptors Allowed
Used Data Buffer Space
Main Offboard Memory
(32-Bit Address Space) Internal Chateau Registers
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