Sequencing

A Simple Example:

'{ $STAMP BS2 }

drumnote  VAR  BYTE

'Useful constants for MIDI I/O
baudmode      CON  60    '60 for BS2sx, 12 for BS2
midinoteon    CON  144

'Define voicing constants
kick          CON  35    'kick drum note number

'Define channel constants
drumchan      CON  9     'drums on channel 10

loop:

  PAUSE 400     'sleep for 400 milliseconds ... controls tempo

  drumnote = kick
  SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]

GOTO loop

Design Issues:

Determine the smallest fraction of a beat needed.
Determine the number of beats per "frame" or measure.
Create a repeating frame sequence.
Add variable elements controlled by sensors

A "Piece by Piece" Example:

Start with kick drum on down beats of a 4-beat frame:

'{ $STAMP BS2 }

tick16    VAR  NIB
drumnote  VAR  BYTE

'Useful constants for MIDI I/O
baudmode      CON  60    '60 for BS2sx, 12 for BS2
midinoteon    CON  144

'Define voicing constants
kick          CON  35    'kick drum note number

'Define channel constants
drumchan      CON  9     'drums on channel 10

tick16 = 0

loop:

  PAUSE 100     'sleep for 100 milliseconds ... controls tempo

  IF tick16 = 0 THEN case0
  IF tick16 = 1 THEN case1
  IF tick16 = 2 THEN case2
  IF tick16 = 3 THEN case3
  IF tick16 = 4 THEN case4
  IF tick16 = 5 THEN case5
  IF tick16 = 6 THEN case6
  IF tick16 = 7 THEN case7
  IF tick16 = 8 THEN case8
  IF tick16 = 9 THEN case9
  IF tick16 = 10 THEN case10
  IF tick16 = 11 THEN case11
  IF tick16 = 12 THEN case12
  IF tick16 = 13 THEN case13
  IF tick16 = 14 THEN case14
  IF tick16 = 15 THEN case15

  GOTO inctick16:

  case0:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case1:
    GOTO inctick16
  case2:
    GOTO inctick16
  case3:
    GOTO inctick16
  case4:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case5:
    GOTO inctick16
  case6:
    GOTO inctick16
  case7:
    GOTO inctick16
  case8:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case9:
    GOTO inctick16
  case10:
    GOTO inctick16
  case11:
    GOTO inctick16
  case12:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case13:
    GOTO inctick16
  case14:
    GOTO inctick16
  case15:

  inctick16:

  tick16 = tick16 + 1    'increment wraps every 16 because of NIB size

GOTO loop

Add a closed hi-hat on off-beats:

'{ $STAMP BS2 }

tick16    VAR  NIB
drumnote  VAR  BYTE

'Useful constants for MIDI I/O
baudmode      CON  60    '60 for BS2sx, 12 for BS2
midinoteon    CON  144

'Define voicing constants
kick          CON  35    'kick drum note number
closedhat     CON  42    'closed hi-hat note number

'Define channel constants
drumchan      CON  9     'drums on channel 10

tick16 = 0

loop:

  PAUSE 100     'sleep for 100 milliseconds ... controls tempo

  IF tick16 = 0 THEN case0
  IF tick16 = 1 THEN case1
  IF tick16 = 2 THEN case2
  IF tick16 = 3 THEN case3
  IF tick16 = 4 THEN case4
  IF tick16 = 5 THEN case5
  IF tick16 = 6 THEN case6
  IF tick16 = 7 THEN case7
  IF tick16 = 8 THEN case8
  IF tick16 = 9 THEN case9
  IF tick16 = 10 THEN case10
  IF tick16 = 11 THEN case11
  IF tick16 = 12 THEN case12
  IF tick16 = 13 THEN case13
  IF tick16 = 14 THEN case14
  IF tick16 = 15 THEN case15

  GOTO inctick16

  case0:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case1:
    GOTO inctick16
  case2:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case3:
    GOTO inctick16
  case4:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case5:
    GOTO inctick16
  case6:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case7:
    GOTO inctick16
  case8:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case9:
    GOTO inctick16
  case10:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case11:
    GOTO inctick16
  case12:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case13:
    GOTO inctick16
  case14:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case15:

  inctick16:

  tick16 = tick16 + 1    'increment wraps every 16 because of NIB size

GOTO loop

Throw in a bass ...

'{ $STAMP BS2 }

tick16    VAR  NIB
drumnote  VAR  BYTE
bassnote  VAR  BYTE

'Useful constants for MIDI I/O
baudmode      CON  60    '60 for BS2sx, 12 for BS2
midinoteon    CON  144
midinoteoff   CON  128
midiprogchng  CON  192

'Define voicing constants
kick          CON  35    'kick drum note number
closedhat     CON  42    'closed hi-hat note number
bass          CON  39    'bass program number

'Define channel constants
drumchan      CON  9     'drums on channel 10
basschan      CON  0     'bass on channel 1

'Set voices with ProgramChange messages
SEROUT 15, baudmode, 0, [midiprogchng+basschan, bass]

bassnote = 28
tick16 = 0

loop:

  PAUSE 100     'sleep for 100 milliseconds ... controls tempo

  IF tick16 = 0 THEN case0
  IF tick16 = 1 THEN case1
  IF tick16 = 2 THEN case2
  IF tick16 = 3 THEN case3
  IF tick16 = 4 THEN case4
  IF tick16 = 5 THEN case5
  IF tick16 = 6 THEN case6
  IF tick16 = 7 THEN case7
  IF tick16 = 8 THEN case8
  IF tick16 = 9 THEN case9
  IF tick16 = 10 THEN case10
  IF tick16 = 11 THEN case11
  IF tick16 = 12 THEN case12
  IF tick16 = 13 THEN case13
  IF tick16 = 14 THEN case14
  IF tick16 = 15 THEN case15

  GOTO inctick16:

  case0:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    SEROUT 15, baudmode, 0, [midinoteoff+basschan, bassnote, 64]
    bassnote = 28
    SEROUT 15, baudmode, 0, [midinoteon+basschan, bassnote, 64]
    GOTO inctick16
  case1:
    GOTO inctick16
  case2:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case3:
    GOTO inctick16
  case4:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case5:
    GOTO inctick16
  case6:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case7:
    GOTO inctick16
  case8:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case9:
    GOTO inctick16
  case10:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case11:
    GOTO inctick16
  case12:
    drumnote = kick
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case13:
    GOTO inctick16
  case14:
    drumnote = closedhat
    SEROUT 15, baudmode, 0, [midinoteon+drumchan, drumnote, 64]
    GOTO inctick16
  case15:

  inctick16:

  tick16 = tick16 + 1    'increment wraps every 16 because of NIB size

GOTO loop

And on and on ....