Geeetech

Hi.


First I will ask you to prepare this electronics for several tests.
To do this, disconnect the controller board from the printer, and disconnect the LCD module.

Organize some space on the table.
Prepare the two modules for operation by connecting them with a ribbon cable.
Connect the power supply to this electronic circuit and observe the behavior of the LEDs.
Tell me what's going on.
Then press the reset button. Observe what is happening again.
Report back.

It depends on your description how well I will get to know your situation.

Take one photo with the modules ready to work, and show it here.
If I said something too briefly, don't hesitate to ask.

I forgot about the most important. The controller board prepared for the test can not have any cables and modules connected, except those mentioned by me.

I have read the old messages and previously there was a problem with establishing communication
And you haven't written what kind of problem is tiring you now.

Hi.
I connected the 2 modules and the power. When turning on, the only LEDs that turn on are D13, D14 and D15. When pressing the Reset button, it is the same.

It has nothing more connected than the screen and the power supply.

The previous board did not allow connection to install the Firmware. Support told me it was a factory failure so I had to buy this new one. The other one turned on the same led and the D16, but the Firmware could not be installed.

I attached photos.











Regards

Hi.

At the moment, LED lights will be the most interesting:
D15,
D16,
D7.

_kaktus_ wrote: Sat Jun 23, 2018 8:03 pm ...
D15 - VCC 5V, red, indicates the presence of voltage 5V0 DC for control electronics, with current capacity up to 3A
Correct condition - Lights up intensively,
D16 - VCC 3V3, red, indicates the presence of 3V3 DC voltage for the control electronics, with current capacity up to 1A
Correct condition - Lights up intensively,
...
D7 - red, indicates that the bootloader is activated
Correct condition: Not lit - Normal operation of the printer,
lights up solidly, the bootloader has been activated to update the printer's firmware,

In addition, I will explain: LED D7 after switching on the power supply should light up and turn off after a little while

From the description which I attached above you already know that LEDs D15 and D16 confirm the correct power supply status of the logical part of the circuit. In your case we do not have a confirmation of LDO 3V3 stabilizer operation.

So I'll ask you to take a few measurements.
I hope that in the meantime you have managed to get acquainted with the topic: kaktus' guide - GTM32 Pro vB controller board - how to read.

• Measurement No. 1.
  Verification of correct operation of LDO stabilizer on the controller board.

  

  GTM32Pro_vB-_pomiary.png (458.56 KiB) Viewed 5633 times

• Measurement No. 2.
  Verification of correct operation of LDO stabilizer on the control panel.

Since I don't know which version of the module you got, I can say: proceed in the same way when measuring.

• Additional measurement.

Disconnect the control panel module from the controller board, retest the presence of 3.3V voltage.

Additionally, check that the stabilizer heats up.
You can do this by touching it with your finger, but be very careful because it can be hot.
Also examine the main µC in this respect.

Outputs of 3.3V LDO stabilizers in our system are connected. This is not the best solution, but you have to be aware of it during measurements.

In case when the stabilizer on the controller board will not give the correct voltage, it must be replaced with a working one.
Alternatively, after verification of the topology of the leads, this loan from the LCD module.

Good luck.
I am waiting for the results of the tests.