Ries Twisk / Mbed 2 deprecated JoyStick

HID Joystick - For use with X-Plane or other programs that can read HID JoySticks

Dependencies:   USBDevice mbed-rtos mbed

Fork of JoyStick by Ries Twisk

This is a simple Joystick HID that I use for xplane and a home build yoke + paddels, see this forum with the look and feel of it : http://forums.x-plane.org/index.php?showtopic=70041

The analog input are filtered with a LowPass IIR filter and the digital input's will be derived from the analog input and de-bounced.

The analog values are read at a 1Khz interval and to ensure we don't push the USB stack to much at a maximum rate of 20 updates/sec HID data is send over USB only if any values where changed. The JoyStick will send 16Bit analog values as opposite of 8 bit values that are normally used to increase accuracy of the whole system. This is well noticeable within x-plane!

The JoyStick uses the JoyStick copied from Wim Huiskamp and modified to suite my needs and the MBED RTOS libraries for reading analog inputs, sending debug data over USB and sending HID data, 3 threads in total.

AutoScale.cpp@5:a0bb17c379ce, 2016-06-22 (annotated)

Committer:
rvt
Date:
Wed Jun 22 12:50:16 2016 +0000
Revision:
5:a0bb17c379ce
Latest

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rvt 5:a0bb17c379ce 1 #include "AutoScale.h"
rvt 5:a0bb17c379ce 2 #include <algorithm>
rvt 5:a0bb17c379ce 3
rvt 5:a0bb17c379ce 4 AutoScale::AutoScale(AnalogFilterInterface *chain,long expectedMin, long expectedMax) :
rvt 5:a0bb17c379ce 5 AnalogFilterInterface(chain), _expectedMax(expectedMax), _expectedMin(expectedMin), _currentMax(expectedMin), _currentMin(expectedMax), _current(0), _a(0.), _b(0), _mul(1.0)
rvt 5:a0bb17c379ce 6 {
rvt 5:a0bb17c379ce 7 }
rvt 5:a0bb17c379ce 8 AutoScale::AutoScale(AnalogFilterInterface *chain,long expectedMin, long expectedMax, double multiplier) :
rvt 5:a0bb17c379ce 9 AnalogFilterInterface(chain), _expectedMax(expectedMax), _expectedMin(expectedMin), _currentMax(expectedMin), _currentMin(expectedMax), _current(0), _a(0.), _b(0), _mul(multiplier)
rvt 5:a0bb17c379ce 10 {
rvt 5:a0bb17c379ce 11 }
rvt 5:a0bb17c379ce 12
rvt 5:a0bb17c379ce 13 AutoScale::~AutoScale()
rvt 5:a0bb17c379ce 14 {
rvt 5:a0bb17c379ce 15 }
rvt 5:a0bb17c379ce 16
rvt 5:a0bb17c379ce 17 void AutoScale::setData(long dataPoint)
rvt 5:a0bb17c379ce 18 {
rvt 5:a0bb17c379ce 19 getChain()->setData(dataPoint);
rvt 5:a0bb17c379ce 20 _current = getChain()->getData();
rvt 5:a0bb17c379ce 21
rvt 5:a0bb17c379ce 22 if (_current < _currentMin) {
rvt 5:a0bb17c379ce 23 _currentMin = _current;
rvt 5:a0bb17c379ce 24 reCalc();
rvt 5:a0bb17c379ce 25 }
rvt 5:a0bb17c379ce 26 if (_current > _currentMax) {
rvt 5:a0bb17c379ce 27 _currentMax = _current;
rvt 5:a0bb17c379ce 28 reCalc();
rvt 5:a0bb17c379ce 29 }
rvt 5:a0bb17c379ce 30 _current = (long)((_a * _current + _b)*_mul);
rvt 5:a0bb17c379ce 31
rvt 5:a0bb17c379ce 32 _current = std::min(_current, _expectedMax);
rvt 5:a0bb17c379ce 33 _current = std::max(_current, _expectedMin);
rvt 5:a0bb17c379ce 34 }
rvt 5:a0bb17c379ce 35
rvt 5:a0bb17c379ce 36 long AutoScale::getData() const
rvt 5:a0bb17c379ce 37 {
rvt 5:a0bb17c379ce 38 return _current;
rvt 5:a0bb17c379ce 39 }
rvt 5:a0bb17c379ce 40
rvt 5:a0bb17c379ce 41 void AutoScale::reCalc()
rvt 5:a0bb17c379ce 42 {
rvt 5:a0bb17c379ce 43 _a = (_expectedMax - _expectedMin) / (double)(_currentMax - _currentMin);
rvt 5:a0bb17c379ce 44 _b = -((_a * _currentMax) - _expectedMax);
rvt 5:a0bb17c379ce 45 }
rvt 5:a0bb17c379ce 46