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This pointer doesn’t move, it always points to the last descriptor.
Initializing device
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Reception Descriptors
NetDev_Start() starts the network interface hardware by initializing the receive and transmit descriptors, enabling the transmitter and receiver and starting and enabling the DMA. Initialization the Rx DMA descriptors list can done in a sub-function NetDev_RxDescInit(). The memory needed by the descriptors must be reserved by the function NetDev_Init(). Initialization of the Rx descriptor list consist of setting the descriptors pointers of the NET_DEV_DATA and fill all Receive descriptors with a Receive buffer.
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