Memory Upload and Download Handling  When larger amounts of memory must be uploaded to the DPU, such as in the case of a software patch or full software upload, the regular memory upload is used.  Memory uploads are accomplished by sending a series of individual D_MEM_DAT_UPLD commands, resulting in a single “virtual” upload. CCSDS-like sequence (grouping) flags are employed to allow the DPU FSW to accept up to a maximum of 65535 bytes in a single “virtual” upload.  The data contained in each D_MEM_DAT_UPLD command is stored in a temporary DRAM buffer until all of the sequence numbers in the entire upload have been successfully received.  When the DPU FSW receives the last command in the series, the FSW will verify that all sequence numbers have been received, verify the end-end upload checksum, and then write the entire temporary buffer to the target location specified in the first upload command.