Quick Start

Motor Tester Example

This example demonstrates a motor tester with:

• Motor control with kick-start and S-curve for realistic driving feel

• Joystick throttle input

• Buttons to adjust curve behavior on the fly

• Non-blocking timer for consistent updates

#include <evaTac.h>
#include <evaHeartbeat.h>
#include <evaJoystick.h>
#include <evaSwitch.h>

#include <evamTA6586Driver.h>
#include <evamDirectionalMotor.h>
#include <evamCurveDecor.h>
#include <evamKickDecor.h>

// Build the motor stack from bottom up:
// Driver (TA6586) -> DirectionalMotor -> KickDecor -> CurveDecor
// 25ms kick pulse at 90% power to overcome static friction
// Negative bend (-6) creates sharper initial response

using BaseMotor = evam::DirectionalMotor<evam::TA6586Driver<9, 10>, -1000, -200, 200, 1000>;
using KickMotor = evam::KickDecor<BaseMotor, 25, 900>;
using PreciseMotor = evam::CurveDecor<KickMotor, -6>;

class Vehicle : public eva::Heartbeat {
private:
  PreciseMotor mMotor;

  // Joystick on A0, signal 100..600 mapped to -1000..1000
  eva::PinSymmetricJoystick<A0, INPUT, 100, 600> mThrottle;

  // Button on pin changes bend (sharper response)
  eva::Handler<Vehicle> mButtonHandler{ this, &onButtonPress };
  eva::PullUpSwitch<3> mButton{ &mButtonHandler, eva::ON_PRESS };

  void onButtonPress(void* sender, eva::CallbackInfo cbInfo) {
    // Softer low-speed response, stronger high-end
    mMotor.SetBend(-mMotor.GetBend());
  }

public:
  Vehicle() : Heartbeat(100) {}

  void onHeartbeat() override {
    // Joystick range (-1000..1000) is compatible with motor range (-1000..1000)
    mMotor.Go(mThrottle.getValue());
  }
};

void setup() {
  // Static ensures object persists after setup() exits
  static Vehicle vehicle;
}

void loop() {
  // Single call drives heartbeat, switches, and motor decorators
  eva::tac();
}

Key Concepts Explained

Motor Stack Composition

The motor is built by stacking components from the bottom up:

CurveDecor        ← Adds S-curve transformation
    ↑
KickDecor         ← Adds kick-start pulse
    ↑
DirectionalMotor  ← Converts -1000..1000 to driver format
    ↑
TA6586Driver      ← Interfaces with hardware (pins 9, 10)

EVA Integration

• eva::tac() drives all time-based components (timer, decorators)

• Heartbeat provides non-blocking periodic updates

• Handler binds events to methods without polling

• PullupSwitch handles button behaviour

For more information please visit eva-core-sk documentation

Customizing Behavior

Parameter	Effect
KickDecor<..., 25, 900>	25ms pulse at 90% power to overcome static friction
CurveDecor<..., -6>	Negative bend = sharper initial response
SetBend(5)	Softer low-speed control, stronger high-end response