== Packet Format == The CRKit packet format is as shown in Figure 1. Host must conform to this specification to enable board level communication. __Figure 1 - Packet Format__ [[BR]][[BR]] [[Image(pkt.jpg, 450px)]] [[BR]][[BR]] The packet consists of following headers : * [wiki:Software/Firmware/Framework/R3_arch/ethernet Ethernet] * [wiki:Software/Firmware/Framework/R3_arch/ip IPv4] * [wiki:Software/Firmware/Framework/R3_arch/udp UDP] * [wiki:Software/Firmware/Framework/R3_arch/tcp TCP] UDP is used for Host <-> CRKit communication e.g. RMAP read/write, status and data transmission. At this point, fragmentation/reassembly at IP level is not yet supported. We may include this feature in the future. Note that the IP packet size must be 46-1500 bytes e.g. size of ethernet payload. Hence, max. UDP payload is 1500 - 20 (IP header) - 8 (UDP header) = 1472 bytes. Furthermore, additional header information is added into the payload region for user specific control information : * [wiki:Software/Firmware/Framework/R3_arch/rmap_pkt RMAP Packet] * [wiki:Software/Firmware/Framework/R3_arch/status_pkt Status Packet] * [wiki:Software/Firmware/Framework/R3_arch/data_pkt Data Packet] Some sample packet configurations : * [wiki:Software/Firmware/Framework/R3_arch/sample_rmap RMAP] * [wiki:Software/Firmware/Framework/R3_arch/sample_data Data] [[BR]][[BR]] [..]