手上買了一個Sharp GP2Y1010AU0F PM2.5的感測器，就只在買來的當下用UNO測試了一下，嗯~~可用，就收起來了，一直到這次要整合在一個能夠顯示時間又有Homekit功能的系統板上(暫且稱它為家庭顯示中心吧)，才又把它拿出來了。
把UNO的code Ctrl+C、Ctrl+V到ESP32下，理論上應該是沒問題的，所以就做啦，只把Delay的部分修改為vTaskDelay，因為我是採用ESP-IDF + RTOS + Arduino 的平台，Flash完，怎麼收到的電壓都是0V，用VR分壓測試，A/D沒問題啊，怎麼沒收到GP2Y的電壓，換回UNO，一切正常啊，甚麼問題???
好，Hardward沒問題，Firmware我只修改Delay，問題不會就在這吧
沒錯，在UNO下的Delay是
delayMicroseconds(280)ESP32是
vTaskDelay(280/portTICK_RATE_MS)這可是差1000倍呀!!
既然在ESP-IDF下已經有支援arduino的套件，那就在這裡也改用delayMicroseconds函數吧，應該不至於影響整個系統太多，畢竟我還有其他task在執行
compiler... flash... run... ，Yes~ got it ，讀到值啦，那就繼續往下一步去，增加到Homekit裝置
新增Homekit裝置時，都需要滿足Apple的service與characteristics定義，但因為我不是ios developer，所以也不知道定義的方式為何，不過沒關係，網路上很多神人的，下面就有一個 characteristics.h 的定義檔可以參考
characteristics.h
用一個開關當範例說明 (參考characteristics.h)
在SERVICE中需要的的是ON這個Characteristics
NAME就列為選項，可有可無了
/**
Defines that the accessory contains a switch.
Required Characteristics:
- ON
Optional Characteristics:
- NAME
*/
#define HOMEKIT_SERVICE_SWITCH HOMEKIT_APPLE_UUID2("49")
而ON這個Characteristics的定義如下
(第6行).permissions中有read、write與notify三個函數
(第9行).value中描述值為BOOL
所以我們共要有三個函數加一個BOOL值
#define HOMEKIT_CHARACTERISTIC_ON HOMEKIT_APPLE_UUID2("25")
#define HOMEKIT_DECLARE_CHARACTERISTIC_ON(_value, ...) \
.type = HOMEKIT_CHARACTERISTIC_ON, \
.description = "On", \
.format = homekit_format_bool, \
.permissions = homekit_permissions_paired_read \
| homekit_permissions_paired_write \
| homekit_permissions_notify, \
.value = HOMEKIT_BOOL_(_value), \
##__VA_ARGS__
回到程式碼中，(第13行)struct hap\_characteristic switch1[]中
switch\_state 就是.value的 BOOL 定義，true 就是switch on，false即為switch off
switch1\_read、switch1\_write與switch1\_notify 就分別是三個函數啦
void *accessory_object = hap_accessory_add(acc);
struct hap_characteristic cs[] = {
{HAP_CHARACTER_IDENTIFY, (void *)true, NULL, identify_read, NULL, NULL},
{HAP_CHARACTER_MANUFACTURER, (void *)MANUFACTURER_NAME, NULL, NULL, NULL, NULL},
{HAP_CHARACTER_MODEL, (void *)MODEL_NAME, NULL, NULL, NULL, NULL},
{HAP_CHARACTER_NAME, (void *)ACCESSORY_NAME, NULL, NULL, NULL, NULL},
{HAP_CHARACTER_SERIAL_NUMBER, (void *)"0123456789", NULL, NULL, NULL, NULL},
{HAP_CHARACTER_FIRMWARE_REVISION, (void *)"1.0", NULL, NULL, NULL, NULL},
};
hap_service_and_characteristics_add(acc, accessory_object, HAP_SERVICE_ACCESSORY_INFORMATION, cs, ARRAY_SIZE(cs));
struct hap_characteristic switch1[] = {
{HAP_CHARACTER_ON, (void *)switch_state,NULL, switch1_read, switch1_write, switch1_notify},
};
hap_service_and_characteristics_add(acc, accessory_object, HAP_SERVICE_SWITCHS, switch1, ARRAY_SIZE(switch1));
switch1\_read、switch1\_write與switch1\_notify 三個函數範例程式如下
void *switch1_read(void *arg)
{
return (void *)switch_state;
}
void switch1_write(void *arg, void *value, int len)
{
switch_state= ((int)value) ? true : false;
if (switch_state)
LED_ON();
else
LED_OFF();
if (_switch1_ev_handle)
hap_event_response(acc, _switch1_ev_handle, (void *)switch_state);
return;
}
void switch1_notify(void *arg, void *ev_handle, bool enable)
{
if (enable)
_switch1_ev_handle = ev_handle;
else
_switch1_ev_handle = NULL;
}
好了，進入主題了，新增PM2.5的Homekit裝置
當我們要使用 air quality 時，需要AIR\_QUALITY的Characteristics，PM2\.5(PM25_DENSITY) 則是列為選項
/**
Defines that the accessory contains a air quality sensor.
Required Characteristics:
- AIR_QUALITY
Optional Characteristics:
- NAME
- STATUS_ACTIVE
- STATUS_FAULT
- STATUS_TAMPERED
- STATUS_LOW_BATTERY
- OZONE_DENSITY
- NITROGEN_DIOXIDE_DENSITY
- SULPHUR_DIOXIDE_DENSITY
- PM25_DENSITY
- PM10_DENSITY
- VOC_DENSITY
- CARBON_MONOXIDE_LEVEL
- CARBON_DIOXIDE_LEVEL
*/
#define HOMEKIT_SERVICE_AIR_QUALITY_SENSOR HOMEKIT_APPLE_UUID2("8D")
來看看 AIR\_QUALITY 的Characteristics
.permissions 列出 read與notitfy
.value 是 0, 1, 2, 3, 4, 5，共六個有效值
#define HOMEKIT_CHARACTERISTIC_AIR_QUALITY HOMEKIT_APPLE_UUID2("95")
#define HOMEKIT_DECLARE_CHARACTERISTIC_AIR_QUALITY(_value, ...) \
.type = HOMEKIT_CHARACTERISTIC_AIR_QUALITY, \
.description = "Air Quality", \
.format = homekit_format_uint8, \
.permissions = homekit_permissions_paired_read \
| homekit_permissions_notify, \
.min_value = (float[]) {0}, \
.max_value = (float[]) {5}, \
.min_step = (float[]) {1}, \
.valid_values = { \
.count = 6, \
.values = (uint8_t[]) { 0, 1, 2, 3, 4, 5 }, \
}, \
.value = HOMEKIT_UINT8_(_value), \
##__VA_ARGS__
PM25\_DENSITY 的Characteristics
.permissions 列出 read與notitfy
.value 是 0~1000 的範圍
#define HOMEKIT_CHARACTERISTIC_PM25_DENSITY HOMEKIT_APPLE_UUID2("C6")
#define HOMEKIT_DECLARE_CHARACTERISTIC_PM25_DENSITY(_value, ...) \
.type = HOMEKIT_CHARACTERISTIC_PM25_DENSITY, \
.description = "PM25 Density", \
.format = homekit_format_float, \
.permissions = homekit_permissions_paired_read \
| homekit_permissions_notify, \
.min_value = (float[]) {0}, \
.max_value = (float[]) {1000}, \
.value = HOMEKIT_FLOAT_(_value), \
##__VA_ARGS__
有上面這些資料，就可以變成我們的code了，範例如下
struct hap_characteristic air_quality[] = {
{HAP_CHARACTER_AIR_QUALITY , (void *)air_quality_value,NULL, air_quality_read, NULL, air_quality_notify},
{HAP_CHARACTER_PM2_5_DENSITY , (void *)pm25_ugm3_value,NULL, pm25_ugm3_read, NULL, pm25_ugm3_notify},
}
hap_service_and_characteristics_add(acc, accessory_object, HAP_SERVICE_AIR_QUALITY_SENSOR , air_quality,ARRAY_SIZE(air_quality));
寫完，收工~~~~~~
