ANTUMBRA ROT8 User manual
ANTUMBRA
ROT8
MANUAL
TABLE OF CONTENTS
01. INSTALLATION 4
02. BACK 5
03. FRONT 6
04. SEQUENCE 7
05. DIRECTION 8
06. GATE PAGE 9
07. STEP SETTINGS 10
08. GATE MODE 11
09. SEQUENCE LENGTH PAGE 12
10. SEQUENCE RESET PAGE 13
11. TUNE PAGE 14
12. GATE LENGTH PAGE 15
13. ASSIGN MENU 16
14. SLEW 17
15. RESET TO DEFAULT 18
16. SOFTWARE MODIFICATIONS 19
00. THANK YOU!
Thank you for purchasing the Antumbra ROT8 module!
In this documentation you can find information about the
installation and use of the module, also an assembly in-
struction if you bought the DIY version.
01. INSTALLATION
POWER CABLE HEADER: Red stripe should be on the
bottom, next to the white marker!
When you turn the ROT8 around, you should see the mod-
ule as it is on the left illustration. Plug in the power cable
to the power cable header pins, but BE CAREFUL with the
orientation of the cable! The RED STRIPE should be on the
BOTTOM of the module, indicated by the white line below
the header pins. By doing otherwise you can potentially
harm the module or even your whole system! Power off
your eurorack system and connect the other end of the
cable to the power source, here also pay attention to the
PSU manufacturer’s instructions!
101
02. BACK
On the back there are two jumpers that can be set.
The top one selects the maximum voltage that goes in the
pots, to the output, this can be set to 5V or 12V.
The bottom one enables or disables the jack lights.
101
03. FRONT
1-8 POTS, LEDS AND BUTTONS PER STEP
(refered to as knob 1, LED 1, button 1, etc.)
9 SLEW POT
10 ASSIGNABLE POT
11 CLOCK IN JACK (0-12V)
12 RESET IN JACK (0-12V)
13 DIRECTION CV IN JACK (0-5V)
14 ASSIGNABLE CV IN JACK (0-5V)
15 GATE OUT JACK (0-5V)
16 CV OUT JACK (0-5V or 0-10V)
A-C BUTTONS
(plus LEDs A, B1-4 and C)
1
2
3
4
5
6
7
8
910
A B C
11 12 13 14 15 16
04. SEQUENCE
The sequence is set by potentiometers 1-8, the value of
the active step (indicated by green LED on LEDs 1-8) is
output on the CV out jack.
The output path is fully analog, so there’s no quantization
on the output.
05. DIRECTION
Direction is indicated by LEDs B1-4, and are cycled by
pressing the B button, or feeding CV into the direction CV
in jack.
The directions from left to right are the following:
B1 Forward (clockwise)
B2 Backward (counter clockwise)
B3 Pendulum
B4 Random
06. GATE PAGE
Gate page is indicated by A and C LEDs being turned off.
You can enter a gate per step by pressing buttons 1-8.
Active gates are represented by red LEDs on each step.
When the sequence reaches a step with a gate set to
on, it’ll output a gate signal on the gate output jack. It’s
length is based on the gate length setting, which will be
explained later in the manual.
07. STEP SETTINGS
Step settings are accessed by long pressing a step button.
The selected step will blink. Buttons in this mode select
the number of repeats on the selected step from 1-8, this
allows you to expand the sequence to more than 8 steps.
To exit the step settings press the selected value one
more time. Now in the gate page the steps with repeat
enabled are going to blink slowly if gate is not enabled on
the step, and will blink quickly if it is.
For gate settings see the next page.
08. GATE MODE
In step settings, button B cycles through gate modes for
the step. The step will only produce gates if it is enabled
on the gate page. The four gate modes are:
B1 SINGLE TRIGGER (default):
There is a single gate output on the step, repeats after it
won’t produce gates.
B2 TRIGGERS:
All triggers of the clock will produce gates.
B3 HOLD:
Gate will go high and will be held open till the last repeat.
B4 RANDOM:
Gates are randomly on or off on each repeat.
09. SEQUENCE LENGTH PAGE
Sequence length page is accessed by pressing button C,
and is indicated by LED C lighting up.
On this page you can set the length of your sequence by
pressing the step buttons. After the last selected step,
the sequence will start again from step 1.
10. SEQUENCE RESET PAGE
Sequence reset page is accessed by long pressing button
C, and is indicated by LED C blinking.
If repeats are enabled, the sequence can go beyond 8
steps, and will likely consist of even steps. On the se-
quence reset page you can constrain the sequence to the
following measures with the step buttons: no constrain,
4, 8, 16, 32, 64, 128, 256
Step numbers
Step count
1 2 3 4 5 6 7 8
1 1 1 1 2 3 4 4
11. TUNE PAGE
You can access the tune page by long pressing on button
A, and is indicated by LED A blinking.
When you access the tune page, the sequence is paused,
and you can change steps by pressing the step buttons.
This is great if you want to tune the knobs to certain po-
sitions.
You can leave this page by pressing button A again.
When you leave this page, the sequence will continue from
the last selected step.
12. GATE LENGTH PAGE
Gate length page is accessed by long pressing button C,
and is indicated by LED C blinking.
Here you can set the gate length with the step buttons.
Gate length is a percentage value calculated from the time
between two clock inputs. The values selectable from this
page are the following:
1 5%
2 13%
3 25%
4 38%
5 50%
6 63%
7 75%
8 88%
13. ASSIGN MENU
Assign menu is accessed by long pressing button B, B1
and B2 LEDs light up. You can switch between CV assign-
ment (B1 & B2 LEDs) and pot assignment (B3 & B4 LEDs)
by pressing button B while in this mode. Leave this page
by long pressing on button B again.
On both pages you can set which parameter is controlled
by CV (coming in on the CV input jack) and pot 10.
If both of them are assigned to the same parameter, pot
10 acts as an offset to the CV signal.
Assignable parameters:
1 Step(0-8): sets the current step to given value.
2 Gatelength(1-95%): sets gate length.
3 Sequencelength(0-8): sets sequence length.
4 Pause(0-1): pauses sequence when input is high.
14. SLEW
The voltage from the step pots are sent through an analog
slew circuit, and then to the output. Slew smooths the
transition between two values, creating glides.
Full counter-clockwise there is no glide effect at all,
while fully clockwise, the transition between two steps is
slowed down.
You probably want to turn this off if you want to use the
output with a quantizer.
NORMAL
SLEW
15. RESET TO DEFAULT
To reset the module to it’s default settings, long press
button A and C, till the B LEDs blink.
Default settings are:
Gate steps: cleared
Repeats: 0
Gate mode: single trigger
Sequence length: 8 steps
Sequence reset: no reset
Gate time: 50%
CV assign: gate length
Pot assign: sequence length
16. SOFTWARE MODIFICATIONS
Feel free to modify the software of your module, but at
your own risk! Antumbra doesn’t take responsibility for
damaged microcontrollers, if you proceed from here I as-
sume you know what you are doing.
If you are unsure of what you are doing, please contact
Antumbra in email at antumbramodular@gmail.com!
Use the 6 pin SPI header on the back to upload code to the
module. You will need an AVR programmer for this.
101
SPI header
Other manuals for ROT8
1
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