 MIDI 2.0 defines a new Universal MIDI Packet format, which contains messages of varying length (32, 64, 96 or 128 bits) depending on the payload type.This new packet format supports a total of 256 MIDI channels, organized in 16 groups of 16 channels; each group can carry either a MIDI 1.0 Protocol stream or new MIDI 2.0 Protocol stream, and can also include system messages, system exclusive data, and timestamps for precise rendering of several simultaneous notes.To simplify initial adoption, existing products are explicitly allowed to only implement MIDI 1.0 messages.