Allwinner A20 - EMAC Operation Diagram

A20 User Manual (Revision 1.2) Copyright © 2013 Allwinner Technology Co., Ltd. All Rights Reserved. Page 741 / 812
6.11.3. EMAC Operation Diagram
6.11.3.1. TX OPERATION
Host Transmit
Frame
TX FIFO
Available
no
CPU Transmit Data
Packet to TX FIFO
yes
TX to MAC Transmit Operation
MAC Operation
Retry
yes
Transmit OK
CPU mode
Transmit fail
yes
no
Abort
no
no
yes
Set DA, SA, length
Registers
DMA Operation