HD6417615 Hitachi Semiconductor, HD6417615 Datasheet - Page 426

• Manufacturer Part Number: HD6417615
• Description: Hardware Manual
• Manufacturer: Hitachi Semiconductor

10.1
The SH7615 has an on-chip two-channel direct memory access controller (E-DMAC) directly
connected to the Ethernet controller (EtherC). A large proportion of buffer management is
controlled by the E-DMAC itself using descriptors. This lightens the load on the CPU and enables
efficient data transfer control to be achieved.
10.1.1
The E-DMAC has the following features:
Note: The E-DMAC cannot handle transfers to supporting modules.
The load on the CPU is reduced by means of a descriptor management system
Transmit/receive frame status information is indicated in descriptors
Achieves efficient system bus utilization through the use of block transfer (16-byte units)
Supports single-frame/multi-buffer operation
Section 10 Ethernet Controller Direct Memory Access
Overview
Features
Controller (E-DMAC)
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