ImuManager¶

Owns the BNO08x IMUs: the onboard one on I2C at 0x4A, and up to three external ones on I2C or SPI. The BNO08x runs its own sensor fusion; this manager creates its handler (which drives the reset and boot lines on the PCAL95555) and optionally wires its data-ready interrupt. Source: ImuManager.h.

Devices¶

Index	Device	Created by
0	Onboard BNO08x (I2C 0x4A)	`ImuManager::EnsureInitialized()`
1 to 3	External BNO08x	You: `CreateExternalBno08xDevice(index, i2c_address, speed_hz)` or `CreateExternalBno08xDevice(index, SpiDeviceId)`

API¶

Call	Notes
`GetBno08xHandler(index = 0)`	`Bno08xHandler*`, or `nullptr`
`VisitSensor(index, fn)`	Runs `fn(IBno08xDriverOps&)` on the driver (enable reports, `Update()`, read the latest data) under the manager and handler locks; `false` if the device is absent or not up
`CreateExternalBno08xDevice(...)`, `DeleteExternalDevice(index)`	External IMUs
`ConfigureInterrupt(index, callback, user_data)`, `EnableInterrupt`, `DisableInterrupt`, `IsInterruptEnabled`, `WaitForInterrupt(index, timeout_ms)`	Data-ready interrupt; the onboard IMU uses `PCAL_IMU_INT` through `GpioManager`. `callback` is a plain `void ()(void)`, called in task context
`IsDeviceValid`, `GetActiveDeviceIndices`, `GetAvailableDevices`, `GetDeviceType`	Device bookkeeping
`GetLastError()`, `GetSystemDiagnostics(ImuSystemDiagnostics&)`, `DumpStatistics()`	Health per device

On the handler, Update() services the SH-2 protocol and dispatches new reports to the callback set with SetSensorCallback(); visitDriver() runs a function on the driver under the handler's lock.

Example: poll the onboard IMU¶

#include "api/Vortex.h"
#include "managers/ImuManager.h"

auto& imu = Vortex::GetInstance().imu;
if (Bno08xHandler* h = imu.GetBno08xHandler(); h != nullptr) {
    // Set a callback once with h->SetSensorCallback(...), then service the device periodically:
    (void)h->Update();
}

The bench app vortex_pcal_gpio_imu_bringup and the manager test encoder_imu_test in Examples show reports being enabled and read.

Diagnostics¶

GetSystemDiagnostics() fills ImuSystemDiagnostics: whether the manager is up, active and initialised device counts, the last error, and a snapshot per device.

Pitfalls¶

The IMU's control lines are on the expander. Reset, boot and interrupt go through the PCAL95555 over I2C, so GpioManager must be up first (the facade orders this).
Call Update() often enough. The BNO08x queues reports; if nothing services it, reports are dropped.
I2C is shared with the PCAL95555. Long I2C transactions from your code delay IMU servicing.