Send gcode via ESP32 to Duet wifi.

A Former User

you can enable telnet and send it over wifi or connect to the paneldue serial port. there are a few posts on the forum that show how to do it.

AverageUser

Yeah I would like to send it over wifi, but with an ESP32. And that is the problem. I dont know where to start. A simple example would save my life ...

A Former User

there are examples in the arduino ide even
https://github.com/espressif/arduino-esp32/blob/master/libraries/WiFi/examples/WiFiClientBasic/WiFiClientBasic.ino

AverageUser

Ohh I know how to make http POST/GET requests with the wifi.h. But how do i channel it to the duet wifi? Do i have to type in the IP-Address of the Duet wifi as the destination for the http request?!?

A Former User

Use the IP address of the Duet.

But instead of HTTP requests you can enable telnet and connect to the telnet port and send GCODE directly instead of dealing with the DWC API

A Former User

i just want a simple led to turn on, when i press a button on the esp32... and it has to be via wlan

in that case the easiest is probably to stick with HTTP towards the IP of your Duet.

first you'll need to set up means to turn your led on and off; by means of a fan output M106 or a gpio M42 (<- click links to learn more)

Then simply sent the HTTP request to run the GCODE needed to turn the LED on.

to use Fan2 output
client.print("GET /rr_gcode?gcode=M106%20P2%20S1 HTTP/1.0\n\n");
or to use M42 with the same Fan2 outut (but not as a fan)
client.print("GET /rr_gcode?gcode=M42%20P22%20S1 HTTP/1.0\n\n");

AverageUser

Thank you very much!!!!

A Former User

simple ESP32 code to send g-code to duet

#include <WiFi.h>
#include <WiFiClient.h>
#include <ESPmDNS.h>


const int led = 5;
const char* ssid     = "ccc";
const char* password = "pass";

//const char* host = "192.168.1.115";
const char* host = "ender5.local.lan";
const int port = 23;
int l = 0;
int potValue = 0;

WiFiClient client;

int sendGcode(char * gcode){
    unsigned long timeout;
    int ret;

    ret = 1;
    
    client.print( String(gcode) + "\r\n" );
    timeout = millis();
    while (client.available() == 0) {
        if (millis() - timeout > 5000) break;
    }
    
    while(client.available()) {
        String line = client.readStringUntil('\r');
        Serial.print(line);
        if (line.startsWith("ok")) ret = 0;
        if (line.startsWith("\nok")) ret = 0;
        if (line.startsWith("\r\nok")) ret = 0;
    }
      
    return(ret);
}




void setup()
{
    pinMode(led, OUTPUT);
    digitalWrite(led, 0);
    Serial.begin(115200);
    delay(10);
    Serial.print("Connecting to ");
    Serial.println(ssid);

    WiFi.config(INADDR_NONE, INADDR_NONE, INADDR_NONE);
    WiFi.mode(WIFI_AP);
    if (MDNS.begin("pendantDue")) {
      Serial.println("MDNS responder started");
    }    
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }
    
    Serial.println("WiFi connected");
    Serial.print("IP address: ");
    Serial.println(WiFi.localIP());

    delay(1000);

    Serial.print("connecting to ");
    Serial.print(host);
    Serial.print(":");
    Serial.println(port);

    if (!client.connect(host, port)) {
        Serial.println("connection failed");
        while(1){
          digitalWrite(led, 0);
          delay(500);
          digitalWrite(led, 1);
          delay(500);
        }
        return;
    }
    
    Serial.print("CONNECTED to ");
    Serial.print(host);
    Serial.print(":");
    Serial.println(port);
}


void loop()
{
    delay(5000);
    sendGcode("M115");
}

AverageUser

@smece thx a lot.. that really saves me from wandering through github and places in the internet where my mind is not suited for. ^^ (smece-- funny name. means garbage in croatian language)

A Former User

@flipil said in Send gcode via ESP32 to Duet wifi.:

smece-- funny name. means garbage in croatian language)

znači i kod nas na istoku

thx a lot.. that really saves me from wandering

you are welcome, I started making a pendant for duet with esp32 so that's the initial test how to talk to it

note that if you don't close the connection client.stop(); it can "block" as it looks like duet is listening only with one or two threads ... you might want to change to open connection to send gcode and immediately close if you don't plan to send many commads

AverageUser

Hvala ti puno smece spasio si mi zivot.

Danal

@bearer said in Send gcode via ESP32 to Duet wifi.:

But instead of HTTP requests you can enable telnet and connect to the telnet port and send GCODE directly instead of dealing with the DWC API

Just note for the future: Telnet is going away in Duet/RepRap V3 firmware.

For that matter, so are RR_whatever HTTP calls. Moving to websocket.

A Former User

@Danal said in Send gcode via ESP32 to Duet wifi.:

For that matter, so are RR_whatever HTTP calls. Moving to websocket.

WHY oh WHY ?!

adding websocket is ok, but removing telnet ?!?!?! why ?

Danal

That was pretty much my question to DC42. Perhaps if we both asked nicely, he'd reconsider.

T3P3Tony

@Danal @smece on Duet 3 you have all the connection options of whatever SBC you use. So SSH into it if you wish.

A Former User

@T3P3Tony said in Send gcode via ESP32 to Duet wifi.:

@Danal @smece on Duet 3 you have all the connection options of whatever SBC you use. So SSH into it if you wish.

so telnet is not going away?

A Former User

@smece said in Send gcode via ESP32 to Duet wifi.:

so telnet is not going away?

with respect to Duet 3 + SBC telnet is already gone, unless you cobble together something like socat and the command line client

A Former User

@bearer said in Send gcode via ESP32 to Duet wifi.:

with respect to Duet 3 + SBC telnet is already gone

dunno what's SBC but I'm running RRF3 on Duet2Eth and telnet is still here

A Former User

@smece said in Send gcode via ESP32 to Duet wifi.:

dunno what's SBC but I'm running RRF3 on Duet2Eth and telnet is still here

Duet 3 as in 3rd generation hardware not firmware, and SBC refers to a single board computer like the raspberry pi.

A Former User

@bearer said in Send gcode via ESP32 to Duet wifi.:

Duet 3 as in 3rd generation hardware not firmware

Yes, of course, but it's firmware that's handling telnet server, and I find it weird that same version RRF3 for duet3 and duet2 is different in that regard.

SBC refers to a single board computer

thanks