Defines a common interface for our effectors.
This library abstracts away effector hardware specifics by defining common configuration and data sturctures and an interface class defining common methods for effectors. This enables the designer of higher-level software to reference this class, rather than individual effector drivers, and have a fixed interface to design against.
CMake is used to build this library, which is exported as a library target called effector. The header is added as:
#include "effector/effector.h"
The library can be also be compiled stand-alone using the CMake idiom of creating a build directory and then, from within that directory issuing:
cmake .. -DMCU=MK66FX1M0
make
This will build the library and an example called example, which has source code located in examples/example.cc. Notice that the cmake command includes a define specifying the microcontroller the code is being compiled for. This is required to correctly configure the code, CPU frequency, and compile/linker options. The available MCUs are:
- MK20DX128
- MK20DX256
- MK64FX512
- MK66FX1M0
- MKL26Z64
- IMXRT1062_T40
- IMXRT1062_T41
These are known to work with the same packages used in Teensy products. Also switching packages is known to work well, as long as it's only a package change.
This library is within the namespace bfs.
inline constexpr int8_t MAX_NUM_EFFECTOR_CH defines the maximum number of effector channels from any one interface, currently set to 32.
inline constexpr int8_t MAX_NUM_SBUS_CH defines the maximum number of effector channels available from SBUS, currently set to 16.
struct EffectorConfig defines the configuration for the Effector object.
| Name | Description |
|---|---|
| std::optional<int8_t> num_ch | The number of effector channels. Currently ignored by SBUS effectors, which allow up to MAX_NUM_SBUS_CH of channels, but necessary for configuring PWM effectors. |
| std::variant<HardwareSerial *, std::array<int8_t, MAX_NUM_EFFECTOR_CH>> hw | Either the hardware serial port used for SBUS effectors or an array pins to be used for PWM effectors |
struct EffectorCmd defines a struct for setting the effector commands.
| Name | Description |
|---|---|
| float cmd[MAX_NUM_EFFECTOR_CH] | Effector commands, normalized to +/-1 |
Effector Concepts are used to define what an Effector compliant object looks like and provide a means to templating against an Effector interface. The required methods are:
bool Config(const EffectorConfig &cfg) Sets the effector configuration. Note that this should just set the configuration options in the effector driver, the configuration is actually applied to the effectors in the Init method. Configuration options should be checked for validity. True is returned on receiving a valid configuration, false on an invalid configuration.
bool Init() This method should establish communication and configure the effectors. True is returned on successfully initializing the effectors.
void Cmd(const EffectorCmd &cmds) Sets the effector commands.
void Write() Sends the commands to the effectors.