SD Specifications Part 1 UHS-II Simplified Addendum - SD Association

UHS-II Simplified Addendum Version 1.01©Copyright 2010-2013 SD Card Association6.2.2.3 Broadcast CCMDBroadcast CCMD operates to all Devices on the bus. On the other hand, CCMD that operates to aspecified Device shown by DID is P2P CCMD.In case of broadcast commands each Device may either transfer commands transparently (e.g.GO_DORMANT_STATE) or make some modifications to the continuing command to the following Node(e.g. ENUMERATE).Features of broadcast CCMD are as follows. Broadcast CCMD issued by Host is represented as DID = SID = 0. In UHS-II Addendum Version1.XX, broadcast packet is only permitted whose TYPE is CCMD and DID = SID = 0. If R/W = 1, broadcast CCMD writes content in its payload to the address in UHS-II I/O spacecalculated from IOADR for all connected Devices. Basically, broadcast CCMD with R/W = 0 is not available, but INQUIRY_CONFIG described inSection 6.2.8.3 is admitted as a special case of broadcast read CCMD. In this case, PLENrepresents its payload length even if R/W = 0. Each Device shall process broadcast CCMD though DID is not equal to its own Node ID, andtransmit it to the next Device or Host. Broadcast CCMD does not accompany RES. So if Host receives broadcast CCMD, Host shallterminate its transaction. If a Device detects some error from broadcast CCMD, it shall not transmit to the next Device orHost. In this case, Host can detect the error by timeout.Note that the broadcast command behavior is the same for all topologies. In case of Hub topology theHub shall emulate a Ring topology in a way that the CCMD shall be transferred in a serial mannerpassing the CCMDs between the Devices through the Hub.47