User manual

7
2 - Use in Pattern Play Mode
(This section and the next do not mention Dynamic Bank/Channel Switching, which is an
elaboration upon the basic 32 Bank Memory system described here.)
If there is no need to switch banks while a pattern is playing, then operation is
straightforward. Simply select the desired memory bank with the toggleswitches and use the
machine normally.
Switching banks while the sequencer is playing patterns enables the creation in real-time of
novel combinations of notes. For instance the first half of a pattern in Bank 8:
▼
▲
▼▼▼
8
could be played, and then by moving the right switch to the up position, the rest of the notes
in that bar of music will come from a pattern in Bank 9:
▼
▲
▼▼
▲
9
Each pattern contains the following information:
• The length of the pattern in steps. This can be between 1 and 16, or 1 to 15 for triplet
mode. After clearing the pattern, hold down the Function button and press the "Step"
button "9" (the same as Transpose Down) once for each note you want in the pattern.
• The "pre-scale", which is typically for 16 notes per 96 clock bar, but can be in triplet
mode for 12 notes per 96 clock bar. After clearing the pattern, it is in 1/16th note
mode, but by holding Function and pressing "0" the pattern is forever set to triplet
mode.
• 16 notes, each of which contains:
o Pitch.
o Accent on/off.
o Slide on/off.
(For the TR-606, each pattern has 1 to 16 beats, each of which can have each drum sound
and accent programmed on or off. Likewise the TR-808, where the A part or the B section
of a pattern can have 1 to 16 beats in its 1st part and 0 to 16 beats in its 2nd part.)
The Internal Sequencer is a single-chip microcontroller (for convenience referred to here as
the “CPU”) connected to what is normally a single bank of memory. With the 32 bank
modification, there are actually 32 banks of memory, and the CPU accesses whichever bank
is currently selected by the toggleswitches and pushbutton. (The switches are de-bounced, so
there are no messy transitions between banks due to mechanical bouncing of switch
contacts.)
When the machine starts playing a pattern, the Internal Sequencer firmware (which is
permanently built into the CPU) reads the length and pre-scale and stores these values in the
CPU's internal RAM. When it comes to play each note (for the TR-606 and TR-808, each
beat), the Internal Sequencer firmware causes the CPU to reads the external memory to
retrieve the note, Accent and Slide information for that note. (For the TR-606 and TR-808,
the CPU reads which drums are to be triggered, and whether Accent is to be set from
external memory just before playing each beat.)
Therefore, by using the five toggleswitches and/or the pushbutton switch to select another
bank of memory in the middle of a pattern, the Internal Sequencer will play subsequent notes