CONSTANT AJAX disconnect errors

[Jarery]

Looking back I think everyone with issues reported using routers with Merlins firmware? Perhaps anyone with Ajax disconnect issues who is running stock firmware on their router could confirm/deny.

Researching Asus routers that drop wireless clients, one thread had success turning off beamforming. In Merlins firmware there are two beamforming settings under "Professional" tab, Explicit and Universal.
Another thread reported wireless client issues dropping with both Merlins and stock firmware but problem cleared when they used DD-WRT firmware.

Last night I turned off both beamforming options. My system has stayed connected overnight. I wont be able to run it through any prints till tomorrow, but perhaps some others with the issue capable of printing sooner could also test and let us know prior to that.

If this route fails I'll start messing with other router firmware. If anyone with issues is using dd-wrt firmware please let me know so i don't go down that path unnecessarily.

[fma]

I'm running an OpenWRT firmware on an APU2 board, and I have these errors. On the other hand, my signal is really weak: -67dB

[KeeganB]

I was running the stock firmware on my Apple Airport Extreme router, and now I am running the stock firmware on my Tenda AC18 router.

I am about 99% sure the Apple router didn't have beam forming.

The Tenda does have beam forming, so I will see if I can turn it off.

Having had the same issues over two different routers and two different network setups I don't think it is a router issue in my case.

I've had a hell of a time with it over the past few days, and my frustration level reached a max last night. I have some new stuff to type up, but I am just not in the frame of mind to do it.

[KeeganB]

If anyone is interested in joining a Slack channel where we can have more instant (and mobile) conversations about this I have created one here:

https://join.slack.com/t/duetwifi/shared_invite/enQtMjY3MDQwOTAwMzc1LWUxMWYwYTg2OWI5NWU3NzI3YWI0ZmRhNGVkMmJjNjU4MTEwZDdjNWQwMTI4Yjk5MGViNWRmNjRiYTQ1NjFmYTY

If you have never used Slack, it is a FANTASTIC messaging system that works on nearly every platform and is loaded with wonderful features for file sharing, images, pics, chat, etc…

EDIT: If this slack channel is well received, we should probably still post to this post to keep everyone that may be following along updated on progress and findings.

[Jarery]

@KeeganB - According to google the apple airport extreme has beamforming. Ive never used their router, perhaps its not able to be turned on/off by the user. No mention if its explicit only or if they implicit also. In my test I've currently turned off both. I also share your pain with the frustration part

@fma, Thanks that helps to know.

[KeeganB]

Jarery,

I'll google it, but my Airport Extreme was from 2008, so it was the older N version, not the newer AC. I'm not sure which one you were looking at.

[Jarery]

dc42, can we get confirmation about the wifi sleep on/off function.

I believe in one thread you said the newest beta firmware turned the sleep option off.
I am using the newest firmware and it responds with "sleep state modem" which from my limited research is still a low powered sleep mode.

Does the newest firmware turn off the sleep ability completely? If not can we get a firmware where it does turn it off ?

*You can use wifi_set_sleep_type to set sleep type for power saving and set NONE_SLEEP_T to disable power saving.
*power saving modes can only be enabled in station mode, since ESP8266 do not sleep when working in softap mode.
*Wake up of sleep:
Deep Sleep: ESP8266 need be waked up by xpd_dcdc(Pin8) or by other gpio of external MCU. Thus, xpd_dcdc(Pin8) or external GPIO should be connected to ext_rstb(Pin32).
Light Sleep and Modem sleep:Both are automatically added by underlying, which can sleep and be waked up automatically. There is no need of any processing in hardware.

[dc42]

It looks like that change failed to make it into 1.20beta2. I am currently working on a new version that uses a later SDK and fixes the KRACK vulnerability, so I'll issue an update when that is finished.

[Jarery]

My beamforming off experimented was a no go. It eventually disconnected.
will wait for the "sleep off" firmware.

[KeeganB]

@Jarery:

My beamforming off experimented was a no go. It eventually disconnected.
will wait for the "sleep off" firmware.

Bummer, I guess one of us should try the firmware downgrade and see if that works. It may at least help narrow down where the issue lies. I don't know if I will have time to get to that tonight, but ill try it after I test a few other things.

One of the things that has been bothering me about this is that sometimes it disconnects and a single click of "Connect" in DWC works fine. Other times it disconnects and locks me out entirely, this is the more common issue. When it does lock me out entirely I can get it to reconnect using one of three different methods. Method three is the most confusing to me.

1. Power the printer/board off and then back on.
2. Send M552 S-1 followed by M552 S1 via Pronterface over USB.
3. Wait. If I click "connect" and it doesn't connect and then I do nothing and just let the printer continue to print or sit idle for "X" amount of minutes I can just click "connect" and it will suddenly connect again. The "X" amount of minutes is generally 30 or more minutes I think.

The common theme among those is that "restarting" the wifi module seems to temporarily fix it, BUT what is happening in scenario #3, where it resolves itself?

[Jarery]

@KeeganB:

1. Power the printer/board off and then back on.
2. Send M552 S-1 followed by M552 S1 via Pronterface over USB.
3. Wait. If I click "connect" and it doesn't connect and then I do nothing and just let the printer continue to print or sit idle for "X" amount of minutes I can just click "connect" and it will suddenly connect again. The "X" amount of minutes is generally 30 or more minutes I think.

The common theme among those is that "restarting" the wifi module seems to temporarily fix it, BUT what is happening in scenario #3, where it resolves itself?

Interesting, I have the same 3 scenarios.
I either turn wifi on/off or wait 30min+.

[KeeganB]

This afternoon when i got home from work, I powered up the printed (NO USB Connected) and figured I would fight with this disconnect issue some more. Here are the steps I took.

1. Power on printer
2. Load DWC in Google Chrome via the hostname.
3. Sigh heavily
4. Walk away, lets get some dinner.

2 MINUTES AND 3 SECONDS is all it stayed connected for. I did nothing but turn it on and load DWC. The heaters were OFF, the steppers were OFF, nothing got homed, no files were uploaded, etc…

I was completely locked out too, This would have required either a power cycle of the printer, or running 552 commands from usb/pronterface.

[MiR]

I yesterday isolated the Duet from interference by first putting two alumnium plates on top of the printer and then placing the Duet above this metal shield, see attached picture.
Later, during a print last night I lost connectivity and could not reconnect. I tried another trick by rebooting my router to check if the Duet reconnects after the WiFi signal is back, it did not. All my other devices reconnected as usual and duet also reconnects when it is not in this 'broken' state.

[dc42]

Keegan, I'd like to send you a Duet WiFi with external antenna to test, to see if it resolves the problem. The antenna will need to be mounted on the outside of your printer, and the cable to the wifi module on the Duet is 13cm long. Will that be workable for you? If so, please PM me with your mailing address.

Also, do you have a 3.3V-compatible USB-to-serial converter? If so then we might be able to get some diagnostics out of the wifi module.

[KeeganB]

@dc42:

Keegan, I'd like to send you a Duet WiFi with external antenna to test, to see if it resolves the problem. The antenna will need to be mounted on the outside of your printer, and the cable to the wifi module on the Duet is 13cm long. Will that be workable for you? If so, please PM me with your mailing address.

Also, do you have a 3.3V-compatible USB-to-serial converter? If so then we might be able to get some diagnostics out of the wifi module.

David,

I would be thrilled to test the external antenna version. 13cm should be plenty of length. I am mounting the Duet where the Rambo was in the Rostock Max, so I should have plenty of distance to run the antenna outside of the melamine frame.

I have a USB-to-serial converter somewhere in an electronics junk drawer. I don't have a clue what the specs are for it. I know it is standard size USB on one end and I think it is 9-pin serial on the other.

I have to ask given the unlucky circumstances with the first replacement duet I received. Is this one a new board, or a "refurbished" board? You'll understand my concern with the used boards.

[KeeganB]

David, sorry I missed it the first time. PM with address sent.

[cbusillo]

I'm not sure if it adds anything to this discussion, but I have an ethernet Duet. I have used different routers and switches and always had disconnects. Its the only thing about this wonderful board that is annoying. I use curl to upload from S3D and it works 100% of the time even when the web interface won't connect.

I keep hoping new firmwares will make it better, but not yet. It seems better on some firmwares, but its hard to tell if thats just me. It seems to help to disconnect the ethernet and reconnect.

[paralepsis]

I think I'm having the same issue that is being reported here. Synopsis of my machine:

• D-Bot, more or less

• 24V Meanwell PS + Anker USB PS for 5V

• Duet Wifi, 1.19.2 firmware

• Duet enclosure is a 3d-printed, open top enclosure sitting outside the frame

On boot, I am typically able to interact normally with the Duet for bed compensation calculation, etc., including preheating hotend and bed. However, typically after I start a print I lose connectivity to the web server, never to return until reboot. Print continues as normal, and I can continue to communicate with the board via USB.

M122 output after last fail:

[[language]]
daemon is idle in state(s) 0
queue is idle in state(s) 0
autopause is idle in state(s) 0
Code queue is empty.
Network state is running
WiFi module is connected to access point
WiFi firmware version 1.19.2
WiFi MAC address 5c:cf:7f:37:8f:14
WiFi Vcc 3.12, reset reason Turned on by main processor
WiFi flash size 4194304, free heap 37848
WiFi IP address 192.168.1.120
WiFi signal strength -55dBm
Reconnections 0
HTTP sessions: 1 of 8
Socket states:  0 0 0 0 0 0 0 0
Responder states: HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)
 

The machine is still a build in progress, so it isn't killing me that this is happening, but if I can somehow contribute to resolving, I'd be happy to.

[dc42]

@cbusillo:

I'm not sure if it adds anything to this discussion, but I have an ethernet Duet. I have used different routers and switches and always had disconnects. Its the only thing about this wonderful board that is annoying. I use curl to upload from S3D and it works 100% of the time even when the web interface won't connect.

I keep hoping new firmwares will make it better, but not yet. It seems better on some firmwares, but its hard to tell if thats just me. It seems to help to disconnect the ethernet and reconnect.

Do the disconnections happen only during printing, or at any time? If they happen only during printing, then next time you get a disconnection during a print, after the print finishes please run M122 and report the MaxReps value in the report. Note, MaxReps is cleared each time you run M122 so only the value you get the first time you run M122 after a print counts.

[KeeganB]

Last night i finally had time to setup the separate router and connect the Duet to it. Very basic setup. network with WPA2 encryption, dhcp IP, no internet access, and no other devices connected to it. Its a rather annoying way to test because I have to switch back and forth networks from my computer, but I may pull an old junk laptop out to do some extended testing.