New Build - M420 error on TFT

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1

Hello lads,
I’ve been reading the 2023 thread for a couple of days:

but I’m not leaving…

I have a Bigtreetech TFT35 V3.0.1 (GD) screen connected to an SKR Pro 1.2.
On the SKR I have your marlin working (with WiFi connection).

Now if I click on home (X-Y) the message appears: "Unknow command: “M420"”
Even though I have installed the TFT firmware version: “No more M420 homing error on the CNC firmware.”
Release 3/22/23 bugfix rollup · V1EngineeringInc/BIGTREETECH-TouchScreenFirmware · GitHub.

I carried out tests both with motors connected and with everything disconnected.

Advice?

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2

Is M420 in your config.ini file?

3

Hi @jeffeb3!

I used the “standard” configuration, so I only have this line commented out:
#custom_gcode_4:M420 S1\n
I would therefore say that I don’t have m420 in the config.

PS: I did another test by installing the last “official” TFT Bigtreetech firmware and even with this I receive error m420 “unknown command”

4

What firmware are you running on the SKR controller (not the tft35)?

Send an M115 and copy the results here.

5

Hi @MakerJim!

Here is a photo of the result of the m115 command:

scr01
scr011641×1120 409 KB

that should be the last.

Thank you! Let me know!

6

The TFT firmware needs to be on Ryan’s latest. The 515 looks fine.

7

Hi,
I installed this:

is this correct?

scr02
scr021635×1120 291 KB

8

That seems like the right one.

9

Hi,
I’ve tried different firmwares for the TFT and I always have the same M420 problem… I don’t know what to invent anymore.

Ideas for me?

10

I finally have the solution!

However strange…

I would like to point out that I have always correctly displayed the TFT update procedure on the screen.

As per the screen posted previously, the installed version was v27.x Feb 15…
which unfortunately is the same name for both version: with m420 bug and the one without.

After reading this thread:

I had the suspicion that the TFT actually wasn’t updating and after installing the version present in this thread, which changes the value of the date, I realized that it actually wasn’t updating!

I formatted the SD with SD formatter, nothing… updated with power off and reset mode, nothing.
The files changed names in the SD card but the firmware did not update.

So, I changed the SD card and the firmware updated successfully and the M420 error disappeared!

I don’t understand why that SD card, which worked correctly for at least 2 updates, created that “fake update”.

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11

I’m glad you figured it out. All I could do was assure you that some version worked.

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