Abstract:
A method of making a package substrate includes providing a cladding sheet comprising a first metal layer, a second metal layer and an intermediate layer between the first and second metal layers; etching away a portion of the first metal layer to expose a portion of the intermediate layer thereby forming a metal island body; laminating a first copper clad on the cladding sheet comprising a first copper foil and a first insulating layer; patterning the first copper foil to form a first circuit trace; patterning the second metal layer to form a second circuit trace; removing the metal island body to form a cavity in the first insulating layer; and removing the intermediate layer from bottom of the cavity.
Abstract:
The invention provides a method improving flexibility of at least one direct memory access (DMA) channel. The at least one DMA channel is used by a plurality of DMA engines of a first device to direct data transmission between the plurality of DMA engines of the first device and a second device. An explanatory embodiment of the method comprises: allowing any of a plurality of DMA engines to use any of the at least one DMA channels, and enabling some of the plurality of DMA engines to share a target channel if some of the plurality of DMA engines simultaneously compete for the target channel, one of the at least one DMA channel.
Abstract:
A packet receiving-transmitting method is provided for use on a packet-switching network, such as Ethernet, for the purpose of handling packets more efficiently than the prior art. By this method, each received packet is stored in a packet buffer of a fixed size and associated with just one descriptor. Based on a threshold logical segmentation size determined by the network protocol, each packet buffer is partitioned into a plurality of segments, each having an ending point linked to an Early Receive/Transmit interrupt signal with the ending point of the packet buffer being linked to an OK interrupt signal. In response to each Early Receive/Transmit interrupt signal, the packet data stored are retrieved and forwarded; and in response to the OK interrupt signal, all the remaining packet data in the packet buffer are retrieved and forwarded. After this a write-back operation is performed on the associated descriptor so as to reset the descriptor to unused status. This method can help allow the memory allocation to each received packet to be more efficient. Moreover, it can help reduce the total number of required interrupts during the receiving-transmitting operation for each received packet, and also can help reduce the total number of descriptor write-back operations for each received packet. This method is therefore significantly more advantageous in terms of system performance than the prior art.