PoC led web with Vaadin 8

Feb 3, 2019

Last Modified: Jan 22, 2024

java 8 arduino vaadin 8 esp8266 at-commands ivan grokhotkov push triac bt136 moc3021 jbang project-reactor fallback nrf24l01 grid-antenna 24dbi
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Summary beginnings

This is an old version that I programmed in 2016 inspired by a post from security by default (post that without it would not be here I can swear).

Where they create a domotic orchard for monitoring tomatoes, peppers with real time graphs, and the help of Javier Salcedo (who hates to be labeled) who helped me to understand the observer/observable pattern (well I’m not very clever either) to notify all the UI’s linked to the session along with websocketska push. understand the observer/observable pattern (well I’m not very clever either) to notify all the UI’s linked to the session along with websockets aka push.

After a while I improved the UI with responsive web design, here the circuit changed a bit, since I used a triac bt136 plus an octoaclopler moc3021.

ArduinoVersionResponsive

Something important to say is that the above has a limitation and it is the following: that the arduino must be connected to the pc by usb if or if, thing that is solved by means of a shield with wifi connection (wireless connection), or a ESP8266, the code between the arduino and vaadin would also change using http requests aka HTTPrequest, to an asynchronous server.

NRF24L01 + PA

ESP8266

I had thought about the NRF24L01 + PA I really see much more advantage over the Esp8266 ESP-01S and it is because you can place an external antenna. I have thought about the NRF24L01 + PA, I really think it has more advantages over the Esp8266 ESP-01S and it is because you can put an external antenna, in the image you can see a 5 dbi omnidirectional antenna it seems, but it is not specified, and it is the least of it, putting a 25dbi grilled directional antenna mmm, something tells me that if you would notice a difference XD, would it be like this? XD, my old configuration that I had in the mother Venezuela, although with what I know now the NRF24L01 is now used for other reasons, together with another one like it, programmed receiver-transeiver

24dbi directional grid antenna

They are more or less the same in real life, quite small both.

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WhatsApp%2BImage%2B2019 06 08%2Bat%2B17.41.07

We’ll have to wait one more week until the rest of them arrive. XD a sad face of drama

To be continued

Back here, on 6/15/2019 an ordinary, typical day.

not bad, right? they are a bit long, well, we remove the atmega328p with care better, an anti-static tweezers.

This is the pinout I am using

An image of how I have the fine connection

We will configure now, the speed to 9600 baud, by default it comes to 115200, we connect to that speed, with NL/CR(new line, and carriage return), we will only remove the 3v voltage, to enter a command, you will see the console output some strange characters.

We enter this command to make it permanent.

AT+UART_DEF=9600,8,1,0,0

With this command we see the version

AT+GMR

We type AT+CWMODE? to see in which mode we are most certainly two. With this command we configure it as station and ap mode.

AT+CWMODE=3

Let’s scan available networks

AT+CWLAP

We connect with

AT+CWJAP="Choristar_5F52","AquiNoEntraNiElDiablo"

When connecting, it should appear in the IDE console…

WIFI CONNECTED
WIFI GOT IP

OK

We configure to accept multiple connections with

AT+CIPMUX=1

We create a server on port 8080.

AT+CIPSERVER=1,8080

Now enter ipconfig/ifconfig to obtain the ip address of the module.

Don’t tell me you believed such a cyber-slut? it really is:

AT+CIFSR

With this java code we can make a HttpRequest with post, using open jdk-11, this is the ip address

Testing native HttpClient of jdk-11

private static final String IP_ESP8266 = "http://192.168.1.45:8080/";

public void hacerPostESP8266() {
    final String pin = JOptionPane.showInputDialog(null,"Introduce On o off");
        if(nonNull(pin)) {
            try {
                final HttpResponse<String> req = HttpClient.newBuilder()
                           .build()
                           .send(HttpRequest (1)
                                    .newBuilder(URI.create(IP_ESP8266 + pin.replaceAll("[\\,\\s+\\.0-9]+","")))
                                    .header("Content-Type", "text/plain; charset=UTF-8")
                                    .POST(HttpRequest.BodyPublishers.ofString(""))
                                    .build(), HttpResponse.BodyHandlers.ofString());
                    LOGGER.info("Estatus code: " + req.statusCode());
                } catch (IOException e) {
                    LOGGER.severe(e.toString());
                } catch (InterruptedException e) {
                    LOGGER.severe(e.toString());
                }
        } else {
                JOptionPane.showMessageDialog(null,"Valor invalido");
        }
}

1	This method is synchronous, but as it is such a fast operation it would not matter much, there is async.

As far as I can see the module sometimes hangs for no reason so when that happens, it will be necessary to set the commands AT commands for multi-connection server, and activate the ip with port like this, it’s bull shit but that’s all there is in the meantime.

AT+CIPMUX=1

AT+CIPSERVER=1,8080

We will have to improve this, because the ESP8266 module can be flashed with a firmware to program it with the arduino IDE thanks to a Russian Ivan Grokhotkov who ignited the spark, here is the repo ESP8266 repo

Update

Another way to execute a request

This example is with project reactor, it could give a way to make an asynchronous request and by the way using jbang equally with the native HttpClient.

You have 2 Url to get the public ip, it would be the same but changing it to local and modifying a little to do POST,
Then if a url fails for some reason, we execute a fallback.

In the following link, flashee my ESP8266

Flashear Esp8266, fucK AT-commands