34
BeatBuddy Manual
MIDI and the BeatBuddy
III.
Tempo Control
•
Since the BeatBuddy’s tempo ranges from 40BPM - 300BPM, we can’t use just
one CC command to cover the whole range because a CC command can only
have 128 values.
•
There are two ways of changing the tempo.
o
With INC/DEC (increase/decrease) messages which adjust the tempo up or
down by 1 BPM
o
By skipping directly to a specific tempo BPM using the MSB/LSB system,
like in the Song Selection system.
However, it’s a bit more complicated because, unlike the Song
Selection system
where you have dedicated CC commands to
represent the MSB (CC:0) and LSB
(CC:32), there are no dedicated
CC commands for Tempo.
So we use the “NRPN Register” (Non-Registered Parameter Number) which is a
general purpose MSB (CC:99) and LSB (CC:98). All that means is that you can control
multiple parameters on the BeatBuddy using an MSB sequence, which is usually a
series of 3 commands: 2 CC commands and one PC.
This can be used to control tempo, any other parameter, or multiple parameters at
once. Currently we’re only using it to control tempo, but we follow the MIDI
Standard protocol to leave room for further control in the future. Because of this
capability for multiple parameter control, the steps below are followed.
