bl_mcu_sdk/examples/adc/adc_key/main.c

/**
 * @file main.c
 * @brief 
 * 
 * Copyright (c) 2021 Bouffalolab team
 * 
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 * 
 */
#include "hal_adc.h"
#include "hal_gpio.h"


#define KEY0_ADC_VALUE  (0)
#define KEY1_ADC_VALUE  (100)
#define KEY2_ADC_VALUE  (200)
#define KEY3_ADC_VALUE  (300)
#define KEY4_ADC_VALUE  (430)
#define KEY_NO_VALUE    (3000)
#define KEY_MEASURE_OFFSET    (30)

#define KEY_FILTER_NUM  (200)
typedef struct {
    uint32_t vaildKeyNum;
    uint16_t keyValue[KEY_FILTER_NUM];
}adc_keys_status;

adc_channel_t posChList[] = {ADC_CHANNEL8};
adc_channel_t negChList[] = {ADC_CHANNEL_GND};
adc_channel_val_t result_val;

adc_keys_status key_machine;

struct device* adc_key;

uint32_t adc_value[2] = {0};
uint32_t key_voltage  = 0;

/**
 * @brief init adc key machine
 * 
 */
static void key_machine_init(void){
    key_machine.vaildKeyNum = 0;
    memset(key_machine.keyValue,0xff,KEY_FILTER_NUM*2);
}

/**
 * @brief Get the adc value range object
 * 
 * @param Vmv input adc value ,unit is mV
 * @return uint16_t 
 */
static uint16_t get_adc_value_range(uint32_t Vmv){
    
    if(Vmv > KEY4_ADC_VALUE - KEY_MEASURE_OFFSET && Vmv < KEY4_ADC_VALUE + KEY_MEASURE_OFFSET){
        return KEY4_ADC_VALUE;
    }else if(Vmv > KEY3_ADC_VALUE - KEY_MEASURE_OFFSET && Vmv < KEY3_ADC_VALUE + KEY_MEASURE_OFFSET){
        return KEY3_ADC_VALUE;
    }else if(Vmv > KEY2_ADC_VALUE - KEY_MEASURE_OFFSET && Vmv < KEY2_ADC_VALUE + KEY_MEASURE_OFFSET){
        return KEY2_ADC_VALUE;
    }else if(Vmv > KEY1_ADC_VALUE - KEY_MEASURE_OFFSET && Vmv < KEY1_ADC_VALUE + KEY_MEASURE_OFFSET){
        return KEY1_ADC_VALUE;
    }else if(Vmv < KEY_MEASURE_OFFSET){
        return KEY0_ADC_VALUE;
    }else{
    	return KEY_NO_VALUE;
    }
}

/**
 * @brief Get the adc key value object
 * 
 * @param Vmv input adc value ,unit is mV
 * @return int 
 */
static int get_adc_key_value(uint32_t Vmv){
	volatile uint16_t key_num[5] = {0};
    uint8_t bigger = 0, i = 0, j = 0;

    if(Vmv >= KEY0_ADC_VALUE && Vmv <= KEY4_ADC_VALUE + KEY_MEASURE_OFFSET){
        key_machine.keyValue[key_machine.vaildKeyNum] = get_adc_value_range(Vmv);
        key_machine.vaildKeyNum++;

        if(key_machine.vaildKeyNum > KEY_FILTER_NUM){
            for(i=0;i<KEY_FILTER_NUM;i++){
                //Count the most Key Value
                switch(key_machine.keyValue[i]){
                    case KEY0_ADC_VALUE:  key_num[0]++; break;
                    case KEY1_ADC_VALUE:  key_num[1]++; break;
                    case KEY2_ADC_VALUE:  key_num[2]++; break;
                    case KEY3_ADC_VALUE:  key_num[3]++; break;
                    case KEY4_ADC_VALUE:  key_num[4]++; break;
                    default : break;
                }
            }
            for(i=0;i<5;i++){
            	for(j=0;j<5;j++){
            		if(key_num[i]>=key_num[j]){
            			bigger = 1;
            		}else{
            			bigger = 0;
            			break;
            		}
            	}
                if(bigger){
                	key_machine_init();
                	return i;
                }
            }

        }
    }
    return KEY_NO_VALUE;

}

// uint32_t sum = 0;
// static uint32_t adc_val_filter(void)
// {
//     static uint32_t cnt_filter = 0;
//     static uint32_t volt_value = 0;

//     volt_value  += adc_value[0];

//     if( ++cnt_filter >= 20)
//     {
//         cnt_filter = 0;
//         key_voltage = (volt_value / 20 * 30 + key_voltage * 70) / 100;
//         volt_value = 0;
//     }
// }

int main(void)
{
    bflb_platform_init(0);
    uint16_t keyValue=0;

    adc_channel_cfg_t adc_channel_cfg;

    adc_channel_cfg.pos_channel = posChList;
    adc_channel_cfg.neg_channel = negChList;
    adc_channel_cfg.num = 1;

    adc_register(ADC0_INDEX, "adc_key", DEVICE_OFLAG_STREAM_RX);

    adc_key = device_find("adc_key");

    if(adc_key)
    {
        ADC_DEV(adc_key)->continuous_conv_mode = ENABLE;
        device_open(adc_key, DEVICE_OFLAG_STREAM_RX);
        device_control(adc_key,DEVICE_CTRL_ADC_CHANNEL_CONFIG,&adc_channel_cfg);
        
    }else{
        MSG("device open failed\r\n");
    }
    
    key_machine_init();
    
    adc_channel_start(adc_key);

    while (1)
    {
        device_read(adc_key,0,(void *)&result_val,1);
        keyValue = get_adc_key_value(result_val.volt * 1000);
        if( keyValue!=KEY_NO_VALUE){
            MSG("key %d pressed\r\n",keyValue);
            MSG("result_val.volt: %0.2f mv\n", (result_val.volt * 1000));
        }
    }
    
}