Imran Sheikh
Using the IDW01M1 board for the STM32 Nucleo F401RE board. This project reads data from Air quality MQ135 click and then read DHT11 values and publish on a private channel on the Thingspeak. A Good example of IoT project with the IDW01 board
Dependencies: DHT11 NetworkSocketAPI X_NUCLEO_IDW01M1v2 mbed
Fork of
AirQuality_Thingspeak
by 
Imran Sheikh
This example project uses IDW01M1 WiFi Module to support IoT projects with example sensors such as Airquality Click MQ135 and DHT11 sensor. The sensor values are then published on the Thingspeak channel. The program uses the DHT11, NetworksocketApi and the SPW library fromX_Nucleo_IDW01M1_v2. This project can easily be adapted to add further sensors or use ESP8266 WiFi module as plenty of support is available on mbed.
Diff: main.cpp
- Revision:
- 13:9a2016106dae
- Parent:
- 12:80d8e97e81f2
--- a/main.cpp Mon Jan 16 13:26:50 2017 +0000
+++ b/main.cpp Sat May 06 17:39:25 2017 +0000
@@ -16,10 +16,22 @@
#include "mbed.h"
#include "SpwfInterface.h"
+//#include "NTPClient.h"
+//#include "HTTPClient.h"
#include "TCPSocket.h"
+#include "DHT11.h"
-
+#define PORT 1234
+#define MAX_PENDING 1
+/*Thing speak settings */
+//NTPClient ntp;
+//HTTPClient http;
+
+//char* ntpServerUrl = "0.ca.pool.ntp.org";
+#define IP "184.106.153.149"
+char* thingSpeakUrl = "http://api.thingspeak.com/update";
+char* thingSpeakKey = "SBYDOEXE50MNOBSI";
//------------------------------------
// Hyperterminal configuration
// 9600 bauds, 8-bit data, no parity
@@ -27,41 +39,84 @@
Serial pc(USBTX, USBRX);
DigitalOut myled(LED1);
-
-/*************************************
-//FRDM-K64: D9->UART1_TX, D7->UART1_RX
-Pin connections:
- FRDM IDW01M1
- ------ ---------
- +3v3 <--> +3v3
- GND <--> GND
- D9 <--> D8
- D7 <--> D2
-
-SpwfSAInterface spwf(D9, D7, false);
-*************************************/
-/*************************************
-//LPCXpresso11U68: D9->UART1_TX, D7->UART1_RX
-Pin connections:
- LPC IDW01M1
- ------ ---------
- +3v3 <--> +3v3
- GND <--> GND
- A1 <--> D8
- A2 <--> D2
-
-SpwfSAInterface spwf(A1, A2, false);
-*************************************/
+AnalogIn ain(A0);
+DHT11 sensor(PA_1);
+/*************************************/
//NUCLEO: D8->UART1_TX (PA_9), D2->UART1_RX (PA_10)
SpwfSAInterface spwf(D8, D2, false);
+const double Rl = 10000.0; // Rl (Ohm) - Load resistance
+const double Vadc_5 = 0.0048828125; // ADC step 5V/1024 4,88mV (10bit ADC)
-int main() {
+//const double Vadc_33 = 0.0032226562; // ADC step 3,3V/1024 3,22mV (10bit ADC)
+double Vrl; // Output voltage
+double Rs; // Rs (Ohm) - Sensor resistance
+double ppm; // ppm
+double ratio;
+int temp;
+int humid;
+
+//Calculation of PPM
+void calculatePPM()
+{
+ double lgPPM;
+ Vrl = (double)ain*Vadc_5; // For 5V Vcc use Vadc_5
+ Rs = (5 - Vrl)/Vrl; // Calculate sensor resistance
+ ratio = Rs/Rl; // Calculate ratio
+ lgPPM = (log10(ratio) * -0.8)+ 0.9; // Calculate ppm
+ ppm = pow(10,lgPPM); // Calculate ppm
+ pc.printf("The ppm value is %lf \n",ppm);
+ pc.printf("The raw Rs is %2.3lf\n",ratio);
+ pc.printf("The raw voltage is %2.3lf \n",Vrl);
+}
+
+int http_demo(void)
+{
+ TCPSocket socket(&spwf);
+ char buffer[256];
+ char message[40];
+ int err;
+ printf("Sending HTTP Data to thingspeak...\r\n");
+
+ // Open a socket on the network interface, and create a TCP connection to thingspeak
+ //socket.open(&spwf);
+ err=socket.connect(IP,80); // connecting to thingspeak
+ if(err!=0)
+ {
+ pc.printf("\r\nCould not connect to Socket, err = %d!!\r\n", err);
+ return -1;
+ } else pc.printf("\r\nconnected to host server\r\n");
+ // Send a simple http request
+ //buffer[0] = 0;
+ //sprintf(buffer, "GET https://api.thingspeak.com/update?api_key=SBYDOEXE50MNOBSI&field1=%f&field2=%d&field3=%d",(float)ppm,temp,humid);//thingSpeakUrl,thingSpeakKey,
+ sprintf(message,"field1=%f&field2=%d&field3=%d",ppm,temp,humid);
+ printf("Message Length=%d\r\n",(int)strlen(message));
+ sprintf(buffer,"POST /update HTTP/1.1\r\nHost: api.thingspeak.com\r\nConnection: close\r\nX-THINGSPEAKAPIKEY: %s\r\nContent-Type: application/x-www-form-urlencoded\r\nContent-Length: %d\r\n\r\n%s",thingSpeakKey,(int)strlen(message),message);
+ pc.printf("Request to %s\r\n", buffer);
+ //char sbuffer[] = "GET / HTTP/1.1\r\nHost: www.arm.com\r\n\r\n";
+ int scount = socket.send(buffer, (int)strlen(buffer));
+ printf("sent %d [%.*s]\r\n", scount, strstr(buffer, "\r\n")-buffer, buffer);
+
+ // Recieve a simple http response and print out the response line
+ char rbuffer[64];
+ int rcount = socket.recv(rbuffer, sizeof rbuffer);
+ printf("recv %d [%.*s]\r\n", rcount, strstr(rbuffer, "\r\n")-rbuffer, rbuffer);
+
+ // Close the socket to return its memory and bring down the network interface
+ socket.close();
+ return 0;
+}
+
+int main()
+{
int err;
- char * ssid = "STM";
- char * seckey = "STMDemo";
-
- pc.printf("\r\nX-NUCLEO-IDW01M1 mbed Application\r\n");
+ char * ssid = "VM957191-2G";
+ char * seckey = "krzvzkcw";
+ //char buffer[255];
+ //time_t ctTime;
+ //Host server(IpAddr(), 123, ntpServerUrl);
+ //ntp.setTime(server);
+ pc.printf("\r\nAir Quality and Environment monitoring Application\r\n");
pc.printf("\r\nconnecting to AP\r\n");
if(spwf.connect(ssid, seckey, NSAPI_SECURITY_WPA2)) {
@@ -75,42 +130,46 @@
const char *mac = spwf.get_mac_address();
pc.printf("\r\nIP Address is: %s\r\n", (ip) ? ip : "No IP");
- pc.printf("\r\nMAC Address is: %s\r\n", (mac) ? mac : "No MAC");
-
- SocketAddress addr(&spwf, "st.com");
- pc.printf("\r\nst.com resolved to: %s\r\n", addr.get_ip_address());
-
- pc.printf("\r\nconnecting to http://4.ifcfg.me\r\n");
-
- TCPSocket socket(&spwf);
- err = socket.connect("4.ifcfg.me", 23);
- if(err!=0)
- {
- pc.printf("\r\nCould not connect to Socket, err = %d!!\r\n", err);
- return -1;
- } else pc.printf("\r\nconnected to host server\r\n");
-
- char buffer[100];
- int count = 0;
- pc.printf("\r\nReceiving Data\r\n");
- count = socket.recv(buffer, sizeof buffer);
+ pc.printf("\r\nMAC Address is: %s\r\n", (mac) ? mac : "No MAC");
- if(count > 0)
- {
- buffer [count]='\0';
- printf("%s\r\n", buffer);
+ while(1)
+ {
+ wait(20);
+ myled = !myled;
+ calculatePPM();
+ err = sensor.readData();
+ if (err ==DHT11::OK)
+ {
+ temp=sensor.readTemperature();
+ humid=sensor.readHumidity();
+ pc.printf("\r\nT: %d oC, H: %d\r\n",temp,humid);
+ }
+ else
+ printf("\r\nErr %i \n",err);
+ int err=http_demo();
+ if(err ==0)
+ pc.printf("Thingspeak update completed successfully\r\n");
+ else
+ pc.printf("Error occurred %d\r\n",err);
+ /* buffer[0] = 0;
+ sprintf(buffer, "%s?key=%s&field1=%s&field2=%d&field3=%d", thingSpeakUrl, thingSpeakKey, , (float)ppm,temp,humid);
+ printf("Request to %s\r\n", buffer);
+
+ HTTPText resp;
+ HTTPResult res = http.get(buffer, &resp);
+ if (res == HTTP_OK)
+ {
+ printf("Result :\"%s\"\r\n", resp.gets());
+ }
+ else
+ {
+ printf("Error %d\r\n", res);
+ } */
+
+
+
}
- else pc.printf("\r\nData not received\r\n");
+
+
+}
- pc.printf("\r\nClosing Socket\r\n");
- socket.close();
- pc.printf("\r\nUnsecure Socket Test complete.\r\n");
- printf ("Socket closed\n\r");
- spwf.disconnect();
- printf ("WIFI disconnected, exiting ...\n\r");
-
- while(1) {
- wait(1);
- myled = !myled;
- }
-}