Version migration and firmware differences¶

Check API changes when upgrading the SDK and discover features again after changing firmware. SDK and firmware have separate version numbers; version ordering alone does not determine compatibility.

BLE write chunks and migration from 0.3.x¶

The SDK writes NUS RX in chunks of at most 20 bytes, with a shorter final chunk when necessary. Applications do not configure this size, and it does not disable Windows, Bleak or system MTU negotiation. Incoming notifications need not be 20 bytes; PacketStream reconstructs packets from their headers.

Since 0.4.0, NusClient no longer accepts write_chunk_size. Remove it from custom transport code using 0.3.x:

# Old 0.3.x usage, no longer supported
# transport = sdk.NusClient(address=ADDRESS, write_chunk_size=20)

# 0.4.0
transport = sdk.NusClient(address=ADDRESS)
ring = sdk.OpenZiloClient(transport=transport)

Differences between firmware implementations¶

When upgrading from V2.001.0002.0000 to V2.001.0002.0001, update your application for these changes:

• Remote recording and settings: V2.001.0002.0001 adds start, stop, status and configuration of channels, bitrate, gain and duration. V2.001.0002.0000 has none of these APIs.
• Live audio: V2.001.0002.0001 adds live Opus output, which the SDK can decode to PCM. V2.001.0002.0000 transfers files after recording is saved.
• Recording format: V2.001.0002.0000 uses Speex. New recordings in V2.001.0002.0001 use mono/stereo Opus (OP2C), with stereo as the default. The SDK still decodes existing Speex files.
• Save notification: V2.001.0002.0000 pushes 0x0505 after saving. V2.001.0002.0001 notifies with 0x050A, followed by file download. Continue using receive_auto_audio_file() for both.
• IMU: V2.001.0002.0000 requires gesture mode first. V2.001.0002.0001 starts capture on 0x0601 and stops on 0x0603 or disconnect. Subscribe again after reconnecting.
• Button and tap events: V2.001.0002.0001 removes recording/gesture mode switching; single presses only report events. Tap detection runs with the IMU subscription instead of maintaining separate background capture.

See remote recording, live audio, IMU and events for SDK usage.