implement SensorStation

3 files changed, 128 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
index 42c6dff..2966f58 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,3 +9,4 @@
 *.out
 *.run.xml
 server/server
+*/build
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..089a0f4
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,33 @@
+SENSOR_SRC = SensorStation/SensorStation.ino
+HVAC_SRC = HvacStation/HvacStation.ino
+
+BOARD = esp32:esp32:lilygo_t_display
+PORT = /dev/ttyACM0
+
+CFLAGS = -b ${BOARD}
+UPLOADFLAGS = -p ${PORT} ${CFLAGS}
+
+all: SensorStation/build HvacStation/build
+
+SensorStation/build: ${SENSOR_SRC}
+	arduino-cli compile ${CFLAGS} SensorStation
+	echo "" > $@
+	@echo done
+
+upload_sensor: SensorStation/build
+	arduino-cli upload ${UPLOADFLAGS} SensorStation
+	@echo done
+
+HvacStation/build: ${HVAC_SRC}
+	arduino-cli compile ${CFLAGS} HvacStation
+	echo "" > $@
+	@echo done
+
+upload_hvac: HvacStation/build
+	arduino-cli upload ${UPLOADFLAGS} HvacStation
+	@echo done
+
+monitor:
+	arduino-cli monitor -b ${BOARD} -p ${PORT}
+
+.PHONY: monitor upload_sensor upload_hvac
diff --git a/SensorStation/SensorStation.ino b/SensorStation/SensorStation.ino
new file mode 100644
index 0000000..6fc5f5b
--- /dev/null
+++ b/SensorStation/SensorStation.ino
@@ -0,0 +1,94 @@
+#include <WiFi.h>
+#include <HTTPClient.h>
+#include <DHT.h>
+
+#define nelem(arr) (sizeof(arr) / sizeof(arr[0]))
+
+enum { DHT_PIN = 21 };
+enum {
+	SECOND = 1000,
+	PERIOD = 30*SECOND,
+};
+
+const char ssid[] = "Pixel_6504";
+const char password[] = "zj3av9sjev7ed8j";
+const char domain[] = "hvac.samanthony.xyz";
+const char humidityPath[] = "/humidity";
+const char targetHumidityPath[] = "/target_humidity";
+const char roomID[] = "SNbeEcs7XVWMEvjeEYgwZnp9XYjToVhh";
+
+DHT dht(DHT_PIN, DHT11); // Humidity sensor.
+
+void
+setup(void) {
+	Serial.begin(9600);
+	while (!Serial) {}
+
+	WiFi.begin(ssid, password);
+	Serial.print("Connecting to WiFi...");
+	while (WiFi.status() != WL_CONNECTED) {
+		Serial.print(".");
+		delay(500);
+	}
+	Serial.println(" connected.");
+	Serial.println("IP address: ");
+	Serial.println(WiFi.localIP());
+
+	Serial.print("Initializing DHT11 humidity sensor...");
+	dht.begin();
+	Serial.println(" done.");
+}
+
+void
+loop(void) {
+	float humidity = dht.readHumidity();
+	Serial.printf("Humidity: %.2f %% RH\n", humidity);
+
+	if (send(humidity) != 0)
+		Serial.println("Failed to send humidity to server.");
+
+	delay(PERIOD);
+}
+
+int
+send(float humidity) {
+	if (WiFi.status() != WL_CONNECTED) {
+		Serial.println("WiFi not connected.");
+		return 1;
+	}
+
+	WiFiClient client;
+	HTTPClient http;
+
+	const char *url = humidityURL(humidity);
+	Serial.printf("POST %s...\n", url);
+	http.begin(client, url);
+	int responseCode = http.POST("");
+	http.end();
+	Serial.printf("HTTP response: %d\n", responseCode);
+	if (responseCode != HTTP_CODE_OK)
+		return 1;
+	return 0;
+}
+
+char *
+humidityURL(float humidity) {
+	static char query[256];
+	int n;
+
+	n = snprintf(query, nelem(query), "room=%s&humidity=%.2f", roomID, humidity);
+	if (n >= nelem(query))
+		Serial.println("Humidity query string buffer overflow; truncating.");
+	return url(domain, humidityPath, query);
+}
+
+char *
+url(const char *domain, const char *path, const char *query) {
+	static char buf[512];
+	int n;
+
+	n = snprintf(buf, nelem(buf), "http://%s%s?%s", domain, path, query);
+	if (n >= nelem(buf))
+		Serial.println("URL string buffer overflow; truncating.");
+	return buf;
+}