Connecting the STM32 Blue Pill board to the internet

The previous code snippets sense a sensor to measure the temperature and send the sensed data to the internet.

When the user requests the temperature from the web browser, the STM32 microcontroller will receive a request to blink an LED and consequently link it to our IoT environment created with the ESP8266 Wi-Fi module.

Figure 9.18 shows the connections required to interface the STM32 and the SP-01:

Figure 9.18 – Connecting the STM32 to the internet

Figure 9.19 shows the actual device connections between the STM32 and the SP-01:

Figure 9.19 – Physical connections between the STM32 and SP-01

To complete the connection between the STM32 and the SP-01, we need to add a few lines of code to the Chapter09/wifi script:

const int toInternetPin = 0;

In the preceding line, add a constant to store the input pin used to receive the data from the internet...