How to use M23

Hello there, and sorry for spamming this forum (I have loads of questions about Marlin but Im a bloody newbie).

So my question is, how do I make the M23 command word? My setup is a that I use a Ramps1.4 on a Arduino Mega.
I created a serial connection via pySerial (on my Computer) and want to load a g-code file to my Ramps-Board. Technically it should work by enabeling the SDSUPPORT in configuration.h right?
After that I tried to use the M23 by sending: "M23 C:\Users\username\Desktop\g_file.gcode", but it didnt work...

Is it because of the directory of the file?
Or is it that I have to tell marlin that the SD-card is connected via serial?

Thanks in advance
CDorn

M23 requires 8.3 format names and directories

Also M23 can only open files that are already on the sdcard in the controller

To upload a file to the sdcard you M28 file.txt then send the code file line by line, then close the file with M29

Edited 3 time(s). Last edit at 03/07/2022 06:44AM by Dust.

Okay thanks. That info helped a lot.
But now I there is a new problem with M28. In seems to have a write problem. It does not accept new commands because it wants me to give it the position of the G-Code in the new file. How do I do that?
I read that in some instances people used something like M107*1 or so. Where the star and number tell marlin the position of the g-code line.
But it doesnt work.. any advice?

your getting this error?

"> Error:No Checksum with line number, Last Line: 0
> Resend: 1
> ok"

Because uploading to sd card requires you to use the line and check sum protocol. As you would not want errors on uploading

This is why you should be using a real control program and not just a terminal program

See [reprap.org] for details on the protocol

But basically it is expecting data on the format

N123 [...G Code in here...] *71

Where N starts at 1 and increases each line

the checksum starts with *

You can find a python implementation of calculating the checksum here [reprap.org]

You also need to watch for errors like "Resend: 1" which states that the checksum failed for line 1 and you need to send it again.

Edited 1 time(s). Last edit at 03/09/2022 07:25AM by Dust.

Thanks a lot for that detailed answer!
I will try it out as soon as possible