System and method for packet transmission from fragmented buffer

A system for transferring network packet data stored in memory to an output device, the system comprising:

• a direct memory access (DMA) interface for accessing a set of data words stored in memory, each data word having at least one valid octet to be included in a network packet and each data word being accessed using a DMA address associated with the data word;
• a first in-first out (FIFO) buffer for storing network packet data to be transmitted by the output device;
• and
• an alignment block having at least one alignment register, wherein the alignment register for storing at least one data octet, and wherein the alignment block is adapted to:
• concatenate one or more packet data octets from at least a first data word having at least one packet data octet to be included in a network packet to generate a first sequence of packet data octets having an octet length at least as great as an octet length of a data word;
• store the first sequence of packet data octets in a FIFO buffer operably connected to the output device when the octet length of the sequence of packet data octets is equal to the octet length of a data word;
• and
• store a first subset of packet data octets from the first sequence of packet data octets in the FIFO buffer and store a remaining second subset of packet data octets from the first sequence in an alignment register when the octet length of the first sequence of packet data octets exceeds the octet length of a data word, wherein an octet length of the first subset of packet data octets is equal to the octet length of a data word.

A system for transferring network packet data stored in memory to an output device, the system comprising:

• means for accessing a set of data words stored in memory, each data word having at least one valid octet to be included in a network packet and each data word being accessed using a DMA address associated with the data word;
• means for concatenating one or more of the at least one packet data octet having at least one packet data octet to be included in a network packet to generate a first sequence of packet data octets having an octet length at least as great as an octet length of a data word;
• means for storing the first sequence of packet data octets in a FIFO buffer operably connected to the output device when the octet length of the sequence of packet data octets is equal to the octet length of a data word;
• and
• means for storing a first subset of packet data octets from the first sequence of packet data octets in the FIFO buffer and storing a remaining second subset of packet data octets from the first sequence in an alignment register when the octet length of the first sequence of packet data octets exceeds the octet length of a data word, wherein an octet length of the first subset of packet data octets is equal to the octet length of a data word.