rgb_sensor.h

00001 /* Discrete RGB color sensor
00002  *
00003  * - uses single-channel light-dependent resistor (via ADC)
00004  *   and a RGB LED.
00005  * -  compensates background light
00006  *
00007  * Copyright (c) 2014 ARM Limited
00008  *
00009  * Licensed under the Apache License, Version 2.0 (the "License");
00010  * you may not use this file except in compliance with the License.
00011  * You may obtain a copy of the License at
00012  *
00013  *     http://www.apache.org/licenses/LICENSE-2.0
00014  *
00015  * Unless required by applicable law or agreed to in writing, software
00016  * distributed under the License is distributed on an "AS IS" BASIS,
00017  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00018  * See the License for the specific language governing permissions and
00019  * limitations under the License.
00020  */
00021  
00022 #ifndef __RGB_SENSOR_H__
00023 #define __RGB_SENSOR_H__
00024 
00025 #define RGB_MASK 0xFFF
00026 
00027 #ifndef RGB_LED_ON
00028 #define RGB_LED_ON true
00029 #endif/*RGB_LED_ON*/
00030 
00031 #ifndef RGB_OVERSAMPLING
00032 #define RGB_OVERSAMPLING 32
00033 #endif/*RGB_OVERSAMPLING*/
00034 
00035 #ifndef RGB_SENSOR_IGNORE
00036 #define RGB_SENSOR_IGNORE (RGB_OVERSAMPLING/2)
00037 #endif/*RGB_SENSOR_IGNORE*/
00038 
00039 
00040 #ifndef RGB_MAX_ADC_CLK
00041 #define RGB_MAX_ADC_CLK 6000000UL
00042 #endif/*RGB_MAX_ADC_CLK*/
00043 
00044 #define RGB_CHANNELS 4
00045 
00046 typedef struct
00047 {
00048     int red,green,blue;
00049 } TRGB_Channel;
00050 
00051 typedef union
00052 {
00053     TRGB_Channel ch;
00054     int data[3];
00055 } TRGB;
00056 
00057 typedef bool (*TRGB_Callback)(const TRGB &rgb);
00058 
00059 class RGB_Sensor
00060 {
00061     public:
00062       RGB_Sensor(PinName red, PinName green, PinName blue, PinName adc);
00063       ~RGB_Sensor(void);
00064       bool capture(TRGB &rgb);
00065       bool capture(const TRGB_Callback callback);
00066       bool wait(void);
00067     protected:
00068       TRGB_Callback m_callback;
00069       bool m_done;
00070       uint8_t m_adc_channel, m_rgb_channel;
00071       DigitalOut m_red, m_green, m_blue;
00072       int m_adc_filter[RGB_CHANNELS][2], m_adc_filter_pos;
00073       int m_adc_aggregation[RGB_CHANNELS], m_adc_count;
00074       void convert(TRGB &rgb);
00075       int filter(int sample);
00076     private:
00077       static void __adc_irq(void);
00078       void adc_irq(void);
00079       static RGB_Sensor *m_global;
00080 };
00081 
00082 #endif/*__RGB_SENSOR_H__*/