Send gcode via ESP32 to Duet wifi.

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

A Former User

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

and I find it weird that same version RRF3 for duet3 and duet2 is different in that regard.

the difference is when used with the single board computer the Duet doesn't use the ethernet interface, only SPI; ergo Telnet is not an option any more as its not supportd by the software package for the SBC.

(although i havent tested it in stand alone operation if it still support telnet)

A Former User

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

the difference is when used with the single board computer the Duet doesn't use the ethernet interface, only SPI;

makes sense to disable ETH if the communication is moved to SBC .. but then you can telnet to SBC so it's still available

T3P3Tony

@bearer my point was with the SBC you can connect over SSH (i.e. secure telnet) that drops you into the console on the SBC where you can use a tool like CodeConsole to send gcode to The Duet.

So no you are not Telneting directly into the Duet but you have the potential for command line gcode entry.

Of course if you want telnetd specifically (as opposed to sshd) the. You can install telnet on the SBC. Presumably this would only be to connect from clients that don't support SSH?

A Former User

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

but then you can telnet to SBC so it's still available

yes, but no-ish. to get the same functionality to send g-code directly to the socket you'll need some DIY stuff ala socat

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

So no you are not Telneting directly into the Duet but you have the potential for command line gcode entry.

same as above, it'll break something like an ESP8266 client sending g-code, unless you sprinkle some 11 spice and herbs on it or adapt the client. not saying its a problem, just pointing out the difference between telnet with a linux shell and telnet to todays Duet2.

(Edit: If the client support SSH (which rules out the tiniest embedded systems due to resources needed for the encryption, i.e. same reason SSH isn't offered on the Duet2) then SSH is actually easier to combine with CodeConsole as you could pipe data directly to CodeConsole running on the remote system as opposed to telnet to a shell)