1 /*
2  * Author: Jon Trulson <jtrulson@ics.com>
3  * Copyright (c) 2015 Intel Corporation.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining
6  * a copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sublicense, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be
14  * included in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  */
24 
25 #include <iostream>
26 
27 #include "rgbringcoder.h"
28 
29 using namespace std;
30 using namespace upm;
31 
RGBRingCoder(int en,int latch,int clear,int clk,int dat,int sw,int encA,int encB,int red,int green,int blue)32 RGBRingCoder::RGBRingCoder(int en, int latch, int clear, int clk, int dat,
33                            int sw, int encA, int encB, int red,
34                            int green, int blue) :
35   m_gpioEn(en), m_gpioLatch(latch), m_gpioClear(clear), m_gpioClock(clk),
36   m_gpioData(dat), m_gpioSwitch(sw), m_gpioEncA(encA), m_gpioEncB(encB),
37   m_pwmRed(red), m_pwmGreen(green), m_pwmBlue(blue)
38 {
39   m_counter = 0;
40 
41   // enable, set LOW
42   m_gpioEn.dir(mraa::DIR_OUT);
43   m_gpioEn.write(0);
44 
45   // latch
46   m_gpioLatch.dir(mraa::DIR_OUT);
47   m_gpioLatch.write(0);
48 
49   // clear, HIGH
50   m_gpioClear.dir(mraa::DIR_OUT);
51   m_gpioLatch.write(1);
52 
53   // clock
54   m_gpioClock.dir(mraa::DIR_OUT);
55   m_gpioClock.write(0);
56 
57   // data
58   m_gpioData.dir(mraa::DIR_OUT);
59   m_gpioData.write(0);
60 
61   // switch
62   m_gpioSwitch.dir(mraa::DIR_IN);
63   m_gpioSwitch.mode(mraa::MODE_HIZ);  // no pullup
64   m_gpioSwitch.write(0);
65 
66   // ecoder A interrupt
67   m_gpioEncA.dir(mraa::DIR_IN);
68   m_gpioEncA.mode(mraa::MODE_PULLUP);
69   // EDGE_BOTH would be nice...
70   m_gpioEncA.isr(mraa::EDGE_RISING, &interruptHandler, this);
71 
72   // ecoder B interrupt
73   m_gpioEncB.dir(mraa::DIR_IN);
74   m_gpioEncB.mode(mraa::MODE_PULLUP);
75   // EDGE_BOTH would be nice...
76   m_gpioEncB.isr(mraa::EDGE_RISING, &interruptHandler, this);
77 
78   // RGB LED pwms, set to off
79 
80   // Red led
81   m_pwmRed.period_ms(1);
82   m_pwmRed.write(0.99);
83   m_pwmRed.enable(true);
84 
85   // Green led
86   m_pwmGreen.period_ms(1);
87   m_pwmGreen.write(0.99);
88   m_pwmGreen.enable(true);
89 
90   // Blue led
91   m_pwmBlue.period_ms(1);
92   m_pwmBlue.write(0.99);
93   m_pwmBlue.enable(true);
94 
95   // whew.
96 }
97 
~RGBRingCoder()98 RGBRingCoder::~RGBRingCoder()
99 {
100   m_gpioEncA.isrExit();
101   m_gpioEncB.isrExit();
102 
103   // turn off the ring
104   setRingLEDS(0x0000);
105 
106   // Turn of RGB LEDS
107   setRGBLED(0.99, 0.99, 0.99);
108   usleep(100000);
109 
110   // turn off PWM's
111   m_pwmRed.enable(false);
112   m_pwmGreen.enable(false);
113   m_pwmBlue.enable(false);
114 }
115 
interruptHandler(void * ctx)116 void RGBRingCoder::interruptHandler(void *ctx)
117 {
118    upm::RGBRingCoder *This = (upm::RGBRingCoder *)ctx;
119 
120    // From the Sparkfun guys:
121 
122    // enc_states[] is a fancy way to keep track of which direction
123    // the encoder is turning. 2-bits of oldEncoderState are paired
124    // with 2-bits of newEncoderState to create 16 possible values.
125    // Each of the 16 values will produce either a CW turn (1),
126    // CCW turn (-1) or no movement (0).
127 
128    static int8_t enc_states[] = {0, -1, 1, 0, 1, 0, 0, -1,
129                                  -1, 0, 0, 1, 0, 1, -1, 0};
130    static uint8_t oldEncoderState = 0;
131    static uint8_t newEncoderState = 0;
132 
133    // First, find the newEncoderState. This'll be a 2-bit value
134    // the msb is the state of the B pin. The lsb is the state
135    // of the A pin on the encoder.
136    newEncoderState = (This->m_gpioEncB.read()<<1) |
137      (This->m_gpioEncA.read());
138 
139    // Now we pair oldEncoderState with new encoder state
140    // First we need to shift oldEncoder state left two bits.
141    // This'll put the last state in bits 2 and 3.
142 
143    oldEncoderState <<= 2;
144 
145    // Mask out everything in oldEncoderState except for the previous state
146    oldEncoderState &= 0x0c;
147 
148    // Now add the newEncoderState. oldEncoderState will now be of
149    // the form: 0b0000(old B)(old A)(new B)(new A)
150    oldEncoderState |= newEncoderState;
151 
152    // update our counter
153    This->m_counter += enc_states[oldEncoderState & 0x0f];
154 }
155 
setRingLEDS(uint16_t bits)156 void RGBRingCoder::setRingLEDS(uint16_t bits)
157 {
158   // First we need to set latch LOW
159   m_gpioLatch.write(0);
160 
161   // Now shift out the bits, msb first
162   for (int i=0; i<16; i++)
163     {
164       m_gpioData.write( ((bits & 0x8000) ? 1 : 0) );
165 
166       // pulse the clock pin
167       m_gpioClock.write(1);
168       m_gpioClock.write(0);
169 
170       bits <<= 1;
171     }
172 
173   // latch it
174   m_gpioLatch.write(1);
175 }
176 
getButtonState()177 bool RGBRingCoder::getButtonState()
178 {
179   return (m_gpioSwitch.read() ? true : false);
180 }
181 
setRGBLED(float r,float g,float b)182 void RGBRingCoder::setRGBLED(float r, float g, float b)
183 {
184   m_pwmRed.write(r);
185   m_pwmGreen.write(g);
186   m_pwmBlue.write(b);
187 }
188