Hi, I try to understand the purpose of the PRE sync (BUS_DMASYNC_PREREAD, BUS_DMASYNC_PREWRITE). I understand POST synchronization (BUS_DMASYNC_POSTREAD, BUS_DMASYNC_POSTWRITE) when a device to memory or a memory to device transfert needs to be synchronized. However, what does a synchronization before a transfert mean ? Regards, Vincent