Offlinecontroller MKT TFT 32 constantly disconnected

Software / Firmware
#1

Hello,
I hope someone can help me, for which I am very grateful. For a few months now I have been working with laser technology and have assembled a device for myself. Now I would like to be able to operate the laser not only with the PC. As software I use Lightburn. I would like to be able to start the device offline with this controller.
I have the following problem. I use the CNC firmware 1.0.1 in the MKS TFT 32 to control my MKS-DLC V 2.0 (GRBL 1.1h) for laser engraving. I selected CNC in the config file so that I can also use 3 axes. The baud rate corresponds to that of the controller 115200.
I have not connected the USB input of the controller to the PC. The message “connected” appears in green on the screen. After tapping a button, it turns red “disconnected”.

Thanks in advance again

#2

What type of wire do you have running between the TFT and the DLC board? Is it an 8 pin ribbon, or are you using separate dupont wires? I ask because if the RX and TX pins are reversed, that may happen.

#3

Thank you for the quick reply. I have used the appropriate supplied 8-pin ribbon cable, which is plugged anti-twist. The connection can not be the problem. The interesting thing is, when I connected the PC with Lightburn, the buttons respond, but just an offline operation is not possible.

#4

Yeah, with the DLC board the USB and TFT share the same serial line. When USB is plugged in, you will get erratic connections on the TFT. It’s one, or the other. Not both at the same time.

#5

You might want to try upgrading the firmware on the TFT. Latest firmware (1.0.3) is HERE.

Also, here is a thread I started dealing with GRBL and TFT screens, if you’re interested.

#6

I am very grateful for the tips. I have looked at the thread. Unfortunately, I can not find a clue there for me for my problem.
I have played the latest firmware on the display and still always get the same error screen.
After the start appears first “connected”, but as soon as I e.g. in the menu Move a key press, then appears again “Disconnected”. I have not connected USB.

#7

Hmmm. I’m not sure. I can’t think of anything else at the moment.

#8

Maybe a few infos or considerations that could help.
I noticed that after “disconnected” appeared on the display, after about 45 seconds “connected” appeared again and the game started again from the beginning. Is it possible that there is some kind of lock due to a command. I think I read something like that in your thread. Only unfortunately I do not know myself with the individual commands so well. Do I have to change something in the config file?

#9

It’s possible the init lock alarm is on. This prevents the machine from moving until it is soft reset or homed. You either have to send a $X or home the machine to clear it. Unfortunately, this can’t be done from the TFT. If you comment out the init lock in GRBL before compiling, this may solve your problem. Try connecting USB and sending $X from ugs or pronterface or whatever gcode sender you are using, then try operating from the TFT.

EDIT: sorry, you can home from the TFT, but not send the reset command. But that’s only if you have homing enabled :grin:

#10

The BTT has a console memu to send some rudamentary commands. Or maybe you can add a button for that?

#11

I have entered the reset command $X once via Lightburn’s console and once via the terminal program, but no success.
I have recorded the sent data from the TFT with a terminal program. Error 9 occurs when I have pressed a key in a menu. Then appears “Disconnect” with the error message error 9. If then “Connect” appears the following blocks come.

Grbl 1.1h [’$’ for help]
[MSG:’$H’|’$X’ to unlock]
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
error:9
error:9
error:9
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
ok
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]

#12

Error 9 is a homing cycle error. This is usually caused by the homing cycle being enabled, but not having any homing limit switches, or they are incorrectly wired/configured.

You can disable the homing cycle by typing $22=0 in the terminal.

#13

I have attached my machine settings. Maybe this helps a bit. I also think it is some configuration error that I can’t find. Normally I still had the softlimits and HomingCircle set to true.

grafik
grafik1577×1774 134 KB

#14

I then connected Lightburn again via usb and there the display reacts as it should, the homing position works and also the movement in the corresponding axes (Softlimits and Homecicle I then set again to true). As soon as I have interrupted the usb-connection or close Lightburn, the display is disconnected.