USB connection

[Fedor kr]

Hello. I’m trying to connect Melzi to BeagleBone though USB connection as it says in one of the previous posts (Added WHITELIST=‘/dev/tty(USB|ACM)’ but I still get “This machine is not connected”. I attached a picture of what I did. About two minutes later, Franklin freezes and I have to restart BeagleBone. Looks like I’m missing a step, but I don’t know what I have to do exactly. 

[Ben H]

Hi ,

I’m trying to write this from a mobile view of a desktop site, so apologies for typos etc. 

I haven’t personally used a melzi/beaglebone, so I hadn’t originally replied. Has usually comes around every 3 months or so, so he should reply eventually. I’m glad you’re still pursuing this and have found an advocate in your former teacher. That’s a very valuable thing. 

In the meantime: are you running Franklin manually from the command line? That should provide you with a verbose log of what Franklin is doing - can you record what is outputs before freezing and share that here?

[Fedor kr]

Hi.

I'm trying to control Franklin with a browser just like it was designed originally. The only thing that command line has is login and password and you can type in commands, it does not show anything when I click things in the browser.

I don't know much about programming and how Franklin works, my only goal is to make this printer work without having to learn a programming language. I have an OrangePi Zero 2, which, I think, should work with Melzi, however I really don't know how to install Franklin on it. Appropedia has some instructions on how to do it, but there is one step that I don't know how to do, installing the packages. 

The reason I chose BeagleBone, is because Bas has uploaded images that do not require much programming knowledge to work with. If you have some instructions on how to set it up on OrangePi, or if you know any other user friendly way to make it work, I would appreciate the help.

пятница, 23 сентября 2022 г. в 05:17:02 UTC-6, Ben H:

[Ben Hubbard]

Gotcha - I think that's reasonable. I spent a lot of time battling with the board to get the latest Franklin installed back in June. That conversation with Bas is documented here if you want to read through and give it a shot.

First, though, try this command on your Orange Pi with the Franklin you have currently installed:

journalctl -u franklin.service

and send back what it returns. If you look at this comment from Bas on the conversation linked above (and my comment right above it) it's possible that we had the same issue, so you may want to give this one a try.

[Ben Hubbard]

Forgot to add a little more context - the 'Permission Denied' on /dev/ttyS0 is the primary clue that the sudo permissions were wrong for the _franklin user. When calling visudo, make sure to select 'nano' as your editor - It's a lot easier to work with than vim, because it tells you the keyboard commands for everything at the bottom. It's worth noting that '^' indicates the control key, so '^K' = 'Ctrl + K'

[Dr. Bas Wijnen]

Hi,

On Sat, Sep 24, 2022 at 06:29:39AM -0700, Ben Hubbard wrote:
> Forgot to add a little more context - the 'Permission Denied' on /dev/ttyS0
> is the primary clue that the sudo permissions were wrong for the _franklin
> user.

This is true, but unless you're using a bridge board, it shouldn't be a
problem. Franklin only needs root permissions to upload firmware over a bridge
board. The usb interface works fine without those permissions.

It sounds to me like the computer (BeagleBone or OrangePi) does not recognize
the Melzi, which makes me think it may be broken. You could try plugging it
into a desktop PC or laptop. it should detect it and show up as a new USB
serial port device. I don't know where you would find that in Windows, probably
somewhere in the control panel. Maybe it just gives a popup message without
even doing anything. On Linux, a file named /dev/ttyUSB0 (or /dev/ttyACM0)
should appear. (Or 1, if 0 already exists.)

If it doesn't appear, the Melzi is broken. If it does, it should also be
detected on the mini-computer. So in that case I'd want to take a closer look
at that.

Thanks,
Bas

[Fedor kr]

Hi. I thought the same thing when I first plugged in this whole thing, however I tried 3 different Melzi boards, two of them looked a little different, but right now I have the same one like in the instructions. I burned the first one (BBB was not plugged in), that design had three pins for the limit switches and I accidentally connected positive and negative pins, so I bought exactly the same one and it did not work either. Finally, I bought Melzi Ardentissimo a couple months ago and got the same result: "This machine is not connected." It looks like BBB is able to communicate with Melzi because when I click "detect," it stops the end effector fan. If I click on the "upload" button, it says: "AVR device not responding". I'm thinking maybe I have firmware problems. My computer is able to detect Melzi.

I put in that command (journalctl -u franklin.service), this is what I got:

-- Logs begin at Sat 2016-05-21 22:31:29 UTC, end at Thu 2017-02-16 13:38:39 UTC
Feb 16 13:37:22 athena systemd[1]: Starting LSB: Server for RepRap 3-D printers.
Feb 16 13:37:24 athena franklin[1059]: Starting Server for RepRap 3-D printers:
Feb 16 13:37:24 athena systemd[1]: Started LSB: Server for RepRap 3-D printers.
lines 1-4/4 (END)
-- Logs begin at Sat 2016-05-21 22:31:29 UTC, end at Thu 2017-02-16 13:38:39 UTC. --
Feb 16 13:37:22 athena systemd[1]: Starting LSB: Server for RepRap 3-D printers...
Feb 16 13:37:24 athena franklin[1059]: Starting Server for RepRap 3-D printers: franklin.
Feb 16 13:37:24 athena systemd[1]: Started LSB: Server for RepRap 3-D printers.
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lines 1-4/4 (END)

вторник, 27 сентября 2022 г. в 09:57:34 UTC-6, bwi...@mtu.edu:

[Bas Wijnen]

Ah, so perhaps that is a little confusing: there is a difference between a
machine being disconnected and a Melzi not being found. A Melzi would not be
found when it is broken (or not plugged in). In that case, in the upload/detect
tab, the port will not be available. If you see the port there, it means that
the Melzi is found.

However, that doesn't mean that it works. If the right firmware is not in its
flash memory, the system won't be able to connect to it. In that case, it says
the machine is not connected.

The solution is of course to upload the right firmware. I tried to make that
easy, but unfortunately Arduino has made that incredibly difficult. There are
different bootloaders which communicate at different speeds. There is no way to
detect what speed should be used, other than trial and error.

In the case of the Melzi, there are two different bootloaders that can be used.
A newly bought Melzi will have the "original" bootloader, in all cases I've
seen so far. For our workshops, we installed Optiboot on them, because it makes
flashing a lot faster.

So the bottom line is: you should select the original mighty1284 bootloader and
try to upload. If it doesn't work, try again with optiboot.

If that doesn't work, I think it may help to work this out in a phone call.
Please let me know (privately) when you are available, if you need this. I'm in
the Netherlands (UTC+2) so please try to find a time when I am awake. ;-)

Thanks,
Bas