- Adds an explicit way to set the size of a value's internal buffer,
replacing `ble.gatts_write(handle, bytes(size))` (although that
still works).
- Add an "append" mode for values, which means that remote writes
will append to the buffer.
NimBLE doesn't actually copy this data, it requires it to stay live.
Only dereference when we register a new set of services.
Fixes#5226
This will allow incrementally adding services in the future, so
rename `reset` to `append` to make it clearer.
Internally change the representation of UUIDs to LE uint8* to simplify this.
This allows UUIDs to be easily used in BLE payloads (such as advertising).
Ref: #5186
This is to more accurately match the BLE spec, where intervals are
configured in units of channel hop time (625us). When it was
specified in ms, not all "valid" intervals were able to be
specified.
Now that we're also allowing configuration of scan interval, this
commit updates advertising to match.
This adds two additional optional kwargs to `gap_scan()`:
- `interval_us`: How long between scans.
- `window_us`: How long to scan for during a scan.
The default with NimBLE is a 11.25ms window with a 1.28s interval.
Changing these parameters is important for detecting low-frequency
advertisements (e.g. beacons).
Note: these params are in microseconds, not milliseconds in order
to allow the 625us granularity offered by the spec.
On other ports (e.g. ESP32) they provide a complete Nimble implementation
(i.e. we don't need to use the code in extmod/nimble). This change
extracts out the bits that we don't need to use in other ports:
- malloc/free/realloc for Nimble memory.
- pendsv poll handler
- depowering the cywbt
Also cleans up the root pointer management.