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Revision to WiFi disconnections and AJAX timeout errors

Jason Znack

-[title|WiFi disconnections and AJAX timeout errors]
+[title|WiFi Troubleshooting: Disconnections, AJAX timeout errors, Unable to connect]
* Is the connection stable when the printer is idle, but unreliable when printing? If so then there may be too few CPU cycles to service the network interface, because of an excessive step pulse rate. Check the M122 report after a disconnection during a print, or after completing the print, and look at the MaxReps figure in the Move diagnostics. This value should be kept below about 50. If it is higher, reduce either microstepping (M350) or maximum speed (M203). Please note, MaxReps is reset when you run M122 so only the value the first time you run M122 after a disconnection or completion of a print is significant.
* Also if the connection is stable when the printer is idle but not when printing: could it be temperature-related? Does the disconnection occur when the CPU temperature displayed in DWC reaches a certain value? If so, try cooling the Duet with a fan, if you are not doing so already.
+* If unable to connect to your wireless network at boot up, try deleting all saved wifi networks with M588 "*" (That is, using an asterix for the network name), then re-adding it with M587. For example, M587 S"networkname" P"password".
== How to improve RSSI ==
* Move the printer and your router closer to each other. Avoid having solid walls between them.
* Try a different WiFi channel (see earlier)
-* Consider locating a WiFi repeater in the room with the printer
+* Consider locating a WiFi repeater, or dedicated 2.4Ghz Wireless G router in the room with the printer.
* It's now possible to replace the ESP-12F WiFi module on the Duet by an ESP-07S with external antenna, but this is not an easy modification to make unless you are experienced with hot air SMD rework and have the necessary equipment.
+* Ensure there are no large motors or fans in the area, or wireless telephones, or microwaves, as these can interfere with the 2.4Ghz spectrum.

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