Re: [LAD] ALSA Sequencer timestamp on event without scheduling

Hi Clemens, On 17/09/16 08:42, Clemens Ladisch wrote: It _does_ on MIDI-BLE. See below. The timestamp on MIDI-BLE is part of the BLE packet and represents the time on the peripheral device (the one sending the MIDI message). Which means I can't schedule the event because they are in the past when compared to the central device[1]. It is also acceptable that one BLE packet has multiple MIDI messages with different timestamps (always increasing). This happens in an attempt to lower the latency. To sum up, this is why I can't schedule these events: * We want to deliver these events *ASAP* to the application - scheduling adds latency, a lot; * Timestamps are in the past relative to the central. But I still need the timestamp information. Why? The spec doesn't explain, but it makes sense to believe it is used to have a predictable latency, so if the central device wants to layout these MIDI message, they little or no jitter in between. Thus, to be MIDI compliant, we need to set this timestamp some how on the event. And I think the simplest way, is to use snd_seq_real_time_t on ev.time.time. Any thoughts? [1] Central device represents the one establishing the connection to a Bluetooth GAP peripheral, similar to a host on USB. -- Felipe