Bleep Drum User Guide & Hacking Info

Bleep Drum main page

Guide for Bleep Drum code v003 (also applies to Dam Drum 2.0).

Basics

Output:
The output is mono but comes out as phased stereo when a stereo plug is in.
The tip of the jack is the signal and the signal is ground. The sleeve is unconnected.
This mean’s that when headphones are plugged in it sounds huge but when a mono plug is in it is just mono.
When connecting it to other gear always use a mono 1/8″ cable on the Bleep Drum end.

The left knob controls the pitch of the red pad, the snare.
Right knob controls the blue, tom pad.

Play – Stop and start playback of selected sequence. Light will blink white on the beat.
Record – Start and stop additive recording. Any pad played will be added to the sequence.
Light blinks red.
Tap – Tap tempo
Shift + pad = Change to that color sequence. Light will change to that color.
Shift + tap + right knob = Change tempo with knob.
Shift + Play = Reverses samples
Play + Record = Erase current sequence.

Blue and yellow sequences start with kick on the 1 and 3.

NOISE MODE 30XX

Hold shift while turning on the device. The light will turn green. Hitting shift again will turn it pink and blinky
Green – Pots control the pitch just like normal
Pink – Pots control noise.
All other controls are the same.

MIDI Implementation

Trigger Note – Pitch CC – Pad
C4 – 70 – red tick
D4 – 71 – blue tom
E4 – 72 – clap green
F4 – 73 – yellow kick

(Some DAWs, like FL Studio, seem to be transposing the output up or down and octave. If your device isn’t responding to these keys, try C5, D3, etc.)

G4 – toggle play

A4 – Reverse toggle
Bb4 – Noise toggle
In noise the four ccs change different variables.

C5 – Select blue sequence
D5 – Select yellow sequence
E5 – Select red sequence
F5 – Select green sequence

G3 – MIDI step (This is used to advance the sequence one 32 note. While midi clock is not supported, this can be used to sync with the rate of another device)

MIDI channel select:
with the device off, hold one of the pads down to select a midi channel.
If no pads are held down during power on the Bleep Drum will receive on all MIDI channels.
Red = 1
Blue = 2
Green = 3
Yellow = 4

Importing samples

The Bleep Drum has about 24 kilobytes of space for samples in the program memory. That’s just over a second at 22k samples/sec.
That might not sounds like much but it’s enough for the four pads on the Bleep Drum.

Here’s a guide for adding your own samples:

1

At the beginning of the bleep drum code there are four tables that hold the samples, “kick”, “tick”, “snare”, and “bass”.

Here’s kick.

PROGMEM prog_char kick_table[] =
{
127,127,128,(…..ssssssamplessss…..) 128,128,128,128
};
int kick_length=5744;

You’ll be wanting to replace the bytes in the table with your sample.

2

Audacity is a great program to do the wav manipulation in.
Get your mono sample cropped as small as you can, making sure to start at zero and having a very quick fade out at the end to reduce pops.
Reduce the sample rate to 22kHz and the bit depth to 8. Try playing with the dither options to see what sounds best.

Once it’s ready go to Analyze > Sample data export

3

Now you need to turn that unformatted pile of numbers into something useful.
Open the text file in a spreadsheet program with tab as the separator.
Use this file as an example on how to turn the floats into bytes.
Make a note of how many bytes there are.

4

Now you’ll need to make that last column look like this:

130,134,136,136,136,134,133,130,129………..

You can do this by saving it as a separate .csv or copying it into a text editor and replacing “/n” with “,”.

5

Now you can copy those commas separated bytes into the tables and change the length value.
If the sketch won’t compile you’re probably over the program space. Try removing strings of small numbers (0,3,0,2,0,1,0,1,0,1,1,0,1,0) from the end of your samples if you need to shave off a few bytes. You might also want to start by removing some or all of the default samples so you have the whole second to work with.
You could also change the sample rate by adjusting “OCR2A” in “DDS”.

Modding

Here is a guide to getting your own samples into the Bleep Drum.

The pads on the left side are for future expandability and hacking. Note That in the new MIDI version does not have the tempo trigger input.

To reprogram the device, use a Arduino Duemilanove or UNO with the chip removed. Connect thr RX, TX, reset and ground pins between the Bleep Drum and Arduino board. Now you can upload directly to the device from the Arduino IDE.

io-port

1 – Ground
2 – Tempo output (high pulse every 1/8th)
3 – +5V
4 – Tempo input (low pulse advances 1/8th. Not available on MIDI version)
5 – Trigger yellow
6 – Trigger blue
7 – Trigger red
8 – Trigger green
9 – TX
10 – RX
11 – +9V (Straight from battery)
12 – Reset

When a low pulse is sent to one of the trigger color buttons, that pad is activated.

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