Ramps Fan Extender HELP!!!

Hi all, I recently added a second extruder to my mendelmax 1.5, and have installed the ramps fan extender so that I can control a second fan for it. However, I am having trouble with the firmware that goes along with this upgrade. Here are the two pages I referred to in order to set it up:

[www.geeetech.com]

[www.instructables.com]


After following the instructable and uploading the firmware, I find that my printer stops working completely. The motors stop working, and even the original M106/M107 commands will not cause my first fan to move. I am sure that it is a firmware issue because once I reload my original file, and remove the extenderboard, the printer works just as it did before. If anyone has any idea what may be going on that would help me alot and I would really appreciate it, thanks.

-Isac

Hi Isac,

I'm not entirely sure what could be causing this problem - did you make any other changes besides those shown on the pages you linked? If you can post details of the firmware changes you've made, I'd be happy to take a look and see if I can spot anything out of place.

I recently wrote up a few notes on getting my TinyFan boards working with Marlin - firmware wise this is the same process as getting the RRD Fan Extender working, maybe there's something in there that could help you out. It might be worth starting off from your original firmware again, and making the modifications from the beginning.

So here is the current firmware I have uploaded to the board. The printer works fine until I try to attach the extender board and the power supply, and then it will not work at all and I need to re-upload the firmware again (and restart my computer sometimes). Please let me know if you see any issue. I am almost certain that it has to do with my pin assignments or something of the sort, but since I am very new to this my guess is probably not very reliable. Thanks again, I really do appreciate the help.
-Isac

I realized my reply was just posted as another comment to the thread. I have included my firmware file on that comment. Thanks!

Hi,

To me that fan extension is 100% useless. 3 possibilities :

1, the fans are for extruders, you don't want to control them.
On extruders the cooling fans are meant to be 100% on
to keep the cold end... cold ! So wire that fans with parallel wiring on the permanent 12v.

2, it's for cooling the part, it's pretty the same,
you want to cool the whole part at the same time,
not cooling the part differently from a side.
So, wire the two fans in parallel on the D9 output.



3, it's for an after printing turbo cooling,
with several huge fans directing on the bed
for a fast part removing.
Once again, you don't need to vary the fan speed, it's 100% on.
Just a relay commanded by pins (D4-D5-D6-D11)
and a 12v powering directly from the PSU.

Keep things simple

Otherhand, If it's just to control fans for fun,
I can't see anything wrong with the instructable.

++JM

Jmax,

Sorry, I was not clear in my description as to what I am working with.

My printer is extruding pastes, not plastic. So initially I set up the D9 port to power the extrusion. Now I am looking to incorporate a second paste that can act as a support material, and to do so requires another independent fan port that can be controlled through Gcode.



Chris-Aus3D,

Could you please send me your firmware file that works for the fan extender that you have linked me to? I feel that by looking at your firmware I can debug mine, or just change the extender to the one that you are using. I would really appreciate that.

Thanks

-Isac