v0.1.0 — first public release

op1-sdk v0.1.0 — first public release

Everything needed to add your own synth engines, effects, sequencer tools and other features to the
Teenage Engineering OP-1 (stock firmware R246): a hook-based build pipeline, a C/asm SDK with
simulator test benches, and a feature library.

This release contains no firmware binaries. The SDK never ships TE firmware or anything derived
from it — you supply your own copy of op1_246.op1 and build images locally.

Feature library (the op1plus recipe)

recipes/op1plus.json composes these into one image:

feature	version	what
chordplus	0.3	chord keyboard (shift + insert)
lofi	0.7	chiptune waves + bytebeat synth engine
wheel	0.7	tonewheel organ engine
warp	0.1	8 waves x 16 warps engine
trio	0.1	SID-style 3-oscillator engine
reso	0.3	tuned-string resonator effect
shimmer	0.2	pitch-shifting reverb effect
fxpack	0.4	seven effects behind one FX slot ("fx mix")
drumroll	0.8	drum step sequencer
requantize	3.2	take quantizer + piano roll
engine_plus	2.0	extra parameters for TE's engines

plus shared libraries (enginehost, quantcore) and debug/demo features (key_probe, midi_filter,
fxdiag). Details: docs/features.md and each features/<name>/README.md.

Build the op1plus firmware yourself

1. Get the stock firmware. Download op1_246.op1 (R246) from Teenage Engineering's official
   support/download page and verify it:

   shasum -a 256 op1_246.op1
   # c5315218f825f143b415ca554516541898abee843d3a236df0b54c04e1fb13a9

   The build tools check this hash and refuse any other image.

2. Build the bfin-elf toolchain (binutils 2.43.1, GCC 14.2.0, GDB 16.3) — exact
   configure/make commands are in docs/toolchain.md.

3. Compose the image:

   python3 tools/compose.py recipes/op1plus.json /path/to/op1_246.op1
   # -> build/apps/op1plus/build/op1plus.op1

   Reference: the maintainer's build of this tag (macOS arm64, toolchain per README) is SHA-256
   eca94ada9cb2e2a487d00f82ff59fb5ac1cae0d978fe6d83946625085699f4c0.

4. Flash. OP-1 off → hold COM while switching on → choose Firmware Upload, then:

   python3 tools/flash.py build/apps/op1plus/build/op1plus.op1 --eject

   Restoring stock works the same way with the original op1_246.op1 (te-boot is never modified).

Full test suite: python3 tools/test_all.py.

Make your own feature and share it

• Scaffold: python3 tools/features.py new my_feature --prefix mf_ --author "Your Name"
• Start from examples/ (minimal asm/C hooks) or copy the layout of any features/<name>/.
• Share as a .zip: python3 tools/features.py pack my_feature; others install it with
  features.py install my_feature.zip (standard: docs/feature-package.md).
• Or open a pull request to add it to the library for every SDK user (CONTRIBUTING.md).

Notes

• Images you build contain TE's firmware and are for your own device — do not redistribute
  .op1/.ldr files.
• Not affiliated with or endorsed by Teenage Engineering. Flashing firmware carries a risk;
  proceed at your own responsibility.