The PF&LB K184-13 Software
The sequencer part and therefore also the software is built around a pair of
Atmega8 microcontrollers. The reason for choosing these are: they
are cheap and easily programmable. There are several ic's available in the Atmega family,
differing in pin numbers and available memory. Because of the number of pins used i chose
to use 2 atmega8s. I could have also used one bigger atmega but the atmega8 are by far the cheapest
in the atmega family so i used this one. There's a master ic and a slave ic.
The master poll's all the buttons and rotary switches. Furthermore it is responsible for storing the patterns
and 'listening' to the clock which tells when to issue trigger signals to the sound sources.
TheThe slave ic receives commands from the master ic and either enables or disables leds or send trigger
signals to the analog sound modules. Both ic's communicate over the atmega8's two wire interfaces.
Sequencer Features
Four running modes
- Forward or 'normal' running mode
- Backwards
- Zigzag (forward then backwards), creates nice rhythm variations
- Random
Patterns
Four patterns can be stored in the internal memory. One is able to program one pattern
while another pattern is played, allowing 'live' creation of rhythm patterns. Pattern changes always
happen on bar 1. The pattern can be paused or stopped. In the paused mode the pattern continues at the
position where it was paused while for stopped it restarts at bar 1.
Instrument Trigger
Each sound modules trigger can be programmed on 1 to 16 bars. In contrary to well-known analog drum
synths each sound modules can be accentuated individually.