LED strip flashing on boot (duex5)

Martin1454

Hi, so just a quick question -

I have a small led strip connected to one of the fan connectors on my duex5 - i use the onboard regulator to supply the 12v

Whenever i turn on the duet, the led strip flashes 3-5 times and then just stays off until i turn it on

Is it normal for it to flash on boot? Anything to do about it?
Thanks

gtj0

The fan output is probably set to blip on startup.

Use M106 Px B0 in your config.g where x is the fan number you use.

I also have LEDs connected to my Duex5:

M106 P3 S0 F100 B0 C"Bed LED"
M106 P4 S0 F100 B0 C"Main LED"

https://duet3d.dozuki.com/Wiki/Gcode#Section_M106_Fan_On

dc42

@Martin1454, did you resolve the problem?

Martin1454

@dc42 I added

 ;LED
M106 P7 S0 F100 B0.0 C"LED light"

to my config, but it still does it - Is it because it is on the duex5?

dc42

I can understand it flashing once, but not 3 to 5 times. I've added this to my list to investigate.

dc42

@Martin1454, do all the heater LEDs on the DueX5 also flash 3 to 5 times when you start it up?

deckingman

@dc42 said in LED strip flashing on boot (duex5):

@Martin1454, do all the heater LEDs on the DueX5 also flash 3 to 5 times when you start it up?

David,

I get this on my Duex5. That is to say, all the heater LEDs sometimes (not always) will flash numerous times during boot up. But I don't have anything connected to them so I hadn't noticed it until I looked, after coming across this post. There is another LED at te bottom of the Duet main board that seems to exhibit the same behaviour. Not sure what that LED is - might be bed heater.

If you recall, in another thread I have mentioned that it can take 10 or more seconds for my Duet with Duex5 to boot, either after power on or after a reset from say editing config.g. I also get a sort of double boot which is audible from the hot end fan behaviour. So maybe the OP's issue and mine might be related?

HTH

dc42

~~Please see this post https://forum.duet3d.com/topic/7726/print-buffer-pauses/3. In particular, I think adding the resistors will solve this problem.~~

dc42

On further investigation, I find that adding resistors is irrelevant to this problem. The reason for the flashes is an undocumented feature of the watchdog timer on the ATSAM4E processor, which can cause it to fire spuriously just after it is enabled. This behaviour is very timing sensitive, and the change in firmware startup time caused by adding a DueX board to the configuration was bringing the timing into the window where this problem was triggered.

I have implemented what I believe is a fix in 2.02RC4.

Martin1454

@dc42 Awsome, Will try it

Martin1454

@dc42

it fixed the issue with RC4