Adding the Duet 3 3HC for additional Extruders

dc42

If CAN communication is working, then the LED on the EXP3HC board should blink slowly in sync with the one on the main board.

If instead the LED on the EXP3HC blinks rapidly and continuously, that means the firmware is running but it does not have CAN communication with the main board.

If instead it flashes a number of times, then remains off for a while, then repeats, the number of flashes is an error code.

mrenz999

@dc42 So when I switch it back to all Dip switches off it flashes 4 times, pauses, and again 4 times. I could not find anything that says what the flashes mean.
Is the CAN connection cable a simple ethernet cable ?

Phaedrux

@mrenz999 said in Adding the Duet 3 3HC for additional Extruders:

Is the CAN connection cable a simple ethernet cable ?

https://duet3d.dozuki.com/Wiki/Duet_3_Mainboard_6HC_Hardware_Overview#Section_CAN_FD_Bus_expansion

The CAN BUS is connected via RJ11 and at least 2 core twisted pair, although 6 core RJ11 is more common.

https://duet3d.dozuki.com/Wiki/Getting_Started_With_Duet_3#Section_Error_codes

4 flashes: the bootloader requested a firmware data block from the main board, but the main board didn't respond in time

dc42

It sounds like the CAN connection isn't present. What does the LED do if you set the board address to 1 by setting position 1 of the switch to On?

mrenz999

@dc42 Constant blinking when set to 1. If I set them all off to 0 it gives the 4 blinks, pauses and 4 blinks. Continues that. I verified nothing was in either of the CAN connectors and cleaned the contacts, then replugged it in. Still the same result.

dc42

Is the constant blinking rapid, or is it slow and in sync with the blinking LED on the main board?

If it is rapid blinking, then it sounds to me that you don't have the correct CAN bus wiring. What cable are you using between the MB6HC main board and the EXP3HC expansion board?

mrenz999

@dc42 Rapid blinking. I am using the CAN cable that came with the 3HC when I purchased it from filastruder.

mrenz999

@dc42 I have a DSL cable. Plugged that in and getting the same result. Did I get a bad board ? Is there something else I can try ?

dc42

As you have tried a different cable, I suspect that either the main board or the expansion board has a faulty CAN port. Please contact your supplier and discuss with them whether they wish to try replacing just one of them or would rather you return both of them.

JuJuDelta

Forgive me for stating the obvious, or if you have checked already:

DSL cables come in 2 flavours, 1:1 wiring and cross over.
The first few I grabbed out of my junk box were cross over, didn't work.
Wasted an hour debugging.

1:1 is needed for Duet 3

dc42

Good point! Use a multimeter to check that the two middle pins of the RJ11 connectors are wired straight through.

mrenz999

@dc42 It is correctly wired. Tested both the DSL and the Cable I purchased with the 3HC from filastruder. So the cables aren't the issue.

dc42

Thanks! Please contact Filastruder and see how they want to establish which board has the faulty CAN port. Assuming neither board shows signs of damage, my guess is that it's the MB6HC, because almost all the tests we do on the EXP3HC rely on the CAN port working.

mrenz999

@dc42 Will do. Neither have any visible signs of damage.

mrenz999

@dc42 Emailed filastruder. Filled out the warranty form. Looks like I need to mail it back and then a few days after they receive the board a replacement will be sent out.