MIDI clock
The CrossPad keeps one MIDI clock for everything connected to it. When a computer sends a clock over USB MIDI, the CrossPad follows it. When the computer stops sending, the CrossPad carries on with its own clock at the last tempo.
Following the computer
Section titled “Following the computer”- Tempo. The DAW’s clock (24 ticks per beat) sets the CrossPad’s tempo, measured over the last four beats so that USB timing jitter does not move it.
- A new tempo locks at once. A gap of more than 250 ms between ticks starts the measurement over, so stop, a new tempo and play are followed straight away.
- Transport. The DAW’s Start starts the metronome in time, Continue resumes it, Stop stops it. After a Start the CrossPad waits up to 8 s for the first tick, for a DAW that counts in first.
- On screen. While the DAW drives the tempo, the Sampler’s BPM field turns blue and the top bar’s BPM follows the DAW. Turn the tempo on the DAW, not on the CrossPad.
The CrossPad’s own clock
Section titled “The CrossPad’s own clock”- After 1 s with no tick and no transport message from the computer, the CrossPad keeps the last tempo and runs the clock itself, from the metronome’s BPM.
- The CrossPad’s own Start and Stop (the Sampler and the Sequencer) go out as MIDI Start and Stop, on the metronome’s first beat.
- Each tick is placed on a fixed grid from the start, so small timer delays never add up over a song.
Where the clock goes
Section titled “Where the clock goes”Every tick and transport message, from the computer or from the CrossPad, goes on to a connected Bluetooth MIDI device. It never goes back to the computer it came from.
For app authors
Section titled “For app authors”A DAW’s clock sets the same transport tempo your app reads. See Tempo and transport.