PB204 Sync Sequencer

That is the latest 8 step sequencer for the Paper Bits. One can change steps, speed and the value of two independent CV output. Because it has an external trigger input one can easily synchronize them. It's evan possible to build an 16, 24 or 32 step sequencer out of two, three or more of them.


Manual

set the CV output:
set MODE switch to CV.
To change the output for each step one select a value with the BEAT/CV potentiometer and in pressing the button for the selected step the selected voltage will be assigned to that individual step.
Depending on the CV switch selection it will be independently stored for the output 1 or 2.

set the rhythm
set MODE switch to BEAT.
To change the length of each step one select a value with the BEAT/CV potentiometer and in pressing the button for the selected step the selection will be assigned to that individual step.
It just works if Ex-Trigger is OFF.

set the steps:
To change between 2 and 8 steps one can use the STEP potentiometer.
If one select 1 step the Sync Sequencer goes into the 1 STEP MODE. With the SPEED potentiometer one can now select each individual step. That makes it easy to program the sequencer.

change the speed:
The speed can be set withe the SPEED potentiometer or with an external control voltage. For that the Ex-Speed switch has to be set on ON and with a jumper one can select between BUS 1 and BUS 2 as the CV source.
If the Sync Sequencer is in the STEP 1 MODE instead of the speed the control voltage will change the individual step.

external trigger:
If one wants to use an external trigger signal one has to set the Ex-Trigger switch on ON and then use the Gate for the trigger input or instead of the TRIGGER jumper one can attache an jumper wire to the marked pin.


Paper-PCB

Parts

  • Resistors:
  • 8x 220 Ohm
  • 3x 10 kOhm
  • 3x 1 kOhm
  • Capacitors:
  • 2x 22 pF (ceramic)
  • 3x 100 nF (foil)
  • 1x 1 nF (foil)
  • Electrolytic Capacitors:
  • 1x 2200µF
  • 1x 10 µF
  • Diodes:
  • 8x LEDs 3mm
  • Crystal:
  • 1x 16 Mhz
  • IC:
  • Atmega328P-PU
  • Mechanical:
  • 1x 28pin IC socket
  • 1x pin strip 1×14
  • 2x pin header, female 90° 1×3, 1×2
  • 2x pin header, male 90° 1×3, 1×2
  • 9x push buttons (2 pins)
  • 1x mini switch
  • 5x jumpers
  • Potentiometers:
  • 3x 10k

Software

Once you're board is ready, you will need to burn the arduino UNO bootloader on the Atmega chip (some chips already come with a bootloader).
Follow the instructions to burn the bootloader:
burn the bootloader

Insert the chip into the IC socket and connect it to you're computer using a USB to Serial board.
breakout board
more about arduino pro mini
Or use your Arduino for that:
http://paperpcb.dernulleffekt.de/doku.php?id=arduino_clones:serial_adapter

Open the Arduino IDE software on your computer and upload the following code to the board: syncsequencer_03.zip

and voila ready to step!