DrumMachinePO

DrumMachinePO

A simple 16-step sequencer with multi-pattern chaining and Teenage Engineering Pocket Operator sync ability.

DrumMachinePO is an enhanced version of Playdate SDK example - DrumMachine - which is just a single-pattern 16-step sequencer.

It adds the following features on top of the DrumMachine example:

1. Save/Load project
2. Multi-pattern (up to 8).
3. Pattern chaining.
4. BPM/Swing adjustment
5. Pocket Operator (e.g. PO-33 KO!) sync ability.

How to install

Download the  "drummachinepo.pdx.zip" file, then sideload it into the Playdate console.

Use https://play.date/account/sideload/ page for zip file sideloading.

Grid view - Pattern editor

Control info:

D-PAD: Move around the grid.

A: Add/remove note. Hold A+up/down to adjust velocity of each notes. If the focus is on the track name (e.g. "KickDrum"), the A-button press will mute the selected track.

B: Start/Stop playing.

Crank:

• No modifier: change the pattern
• Hold A + crank: change BPM
• Hold B + crank: change Swing amount

Patterns/Settings view

You can access the patterns/settings menu via Playdate System menu.

Control info:

D-PAD: Move around the settings. "up" toggles the chain mode on/off when the highlight is at the top.

A: Select options, or hold to copy pattern (cursor should be on the source pattern. While holding A, press left/right to desired destination patterns)

B: Go back to grid view/delete the pattern chain, or hold to clear pattern.

Syncing with Pocket Operator

When Sync mode is enabled, DrumMachinePO shifts all the drum sounds to the right channel.

Left channel is reserved for the sync signal, which is just a click sound that fires 1,3,5,7... steps.

This is equivalent of Pocket Operator sync mode 1. (SY1)

Since there are no "stereo in" in Playdate, Playdate should be the first one in the chain.

You can access the Sync mode by holding "Function" key and pressing "BPM" key on your Pocket Operator.

Sync mode of Pocket Operators work like the following (from https://www.reddit.com/r/pocketoperators/comments/4h3l8k/sync_modes_explained/):

mode input output

SY0 stereo stereo

SY1 stereo mono/sync --> Playdate runs in this mode

SY2 sync stereo

SY3 sync mono/sync

SY4 mono/sync stereo --> Pocket Operator should be in this mode, if it's the last one in the Sync Chain.

SY5 mono/sync mono/sync --> Pocket Operator should be in this mode, if it's in the middle of the Sync Chain.

As the sync signal is just a mono sound, if the volume is too low it might not get detected by the Pocket Operators.

Also, SY4/SY5 only appears when you connect the line-in cable to the PO.

Source code / GitHub

https://github.com/signfang/DrumMachinePO

License info

Original SDK example of DrumMachine was distributed in 0BSD license. This project - DrumMachinePO - is distributed under MIT license.