described as +5V and GND. You
must not
connect any power to those pins, they
are only for connection end potentiometer taps.
All cables leading from POT scanners to potentiometers should be either shielded or
very short (no more than 30cm). Using long non-shielded cable may generate
spurious MIDI messages when unexpected. Typical microphone cable is good
enough for preventing this, even the low-cost one.
4.1
Analog inputs update rate - #98
All analog inputs of potentiometer scanners (POT12, BBS24, PDS, BBPS) translate
input voltages, or potentiometer position into MIDI. Actual pot position is updated
via MIDI every time it changes. This update is however not immediate - this is
common to any MIDI knob box. The fastest response for potentiometer movement
on a single input is about 5ms. It means that when you constantly move the pot,
MBBS will update the MIDI parameter every 5ms. This is more than enough for
most of uses. In some instruments, either hardware, or virtual, some problem may
occur when there is heavy MIDI load. It is also sometimes desirable to limit MIDI
traffic e.g. to minimize the size of MIDI file recorded in a sequencer. It is possible to
change this setting using command "#98n" from the keypad, where "n" determines
update rate according to the table below. More on how to enter digits and setting
procedures, in chapter 5. Default factory setting is 18ms.
keypad
sequence
#980 #981 #982 #983
#984
#985 #986 #987 #988 #989
pot latency
5ms 7ms 9ms 13ms
18ms
25ms 35ms 50ms 70ms 0.1s
update rate
200Hz 145Hz 115Hz 80Hz
55Hz
40Hz 30Hz 20Hz 15Hz 10Hz
This setting is available for all pot-capable boards (POT12, BBS24, BBSP, PDS)
connected to MBBS board. Each board can have different update rates, but all
inputs in one POT board work with one rate. For example you can set it to 50ms on
first POT scanner, and 13ms on second one (assuming you have 2). As usual, to
change any settings for particular board, select it first by moving a bit any
potentiometer connected to board in question. Then using your keypad enter the
code from above table. New settings will be activated and remembered.
4.2
Bitwise resolution of analog inputs - #96
Usually all MIDI parameters have 128 possible levels, determined by 7 bit nature of
MIDI standard. In some cases it may be useful to reduce the number of possible
levels, or in another words - number of information bits. For example if you want to
use MIDI channel rotary selector, described in chapter 5.2.10, it's better to reduce
resolution to 4 bits, and have only 16 levels in full pot rotation. In some software
synthesizers you can select parameters using only a fraction of the full CC range.
And in organ emulators it's also sometimes desirable to have only a few steps in full
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