Azteeg X3 3D Printer Controller

[cvoinescu]

I've done the same thing with an Arduino Mega 2560 and RAMPS, and simply using a separate USB-to-TTL converter instead of the on-board chip made no difference. However, a separate USB-to-TTL converter and optocouplers between it and the Arduino solved the problem.

[fma]

Did you have to change something at hardware level? Did you remove the integrated FTDI chip? Did you change something in the firmware?

What if not adding the optos? What is the behaviour, in this case?

Thanks for the feedback.

[flickerfly]

According to the wiring diagram, you have RX,TX,5V and Gnd all on J2, which is one of the ones that the expansion board plugs into in the lower left corner under the hot end connections. start with that. It isn't clear which pin is which, but you should be able to tone out 5V and Gnd and then it's guess and check on the other two. It is definitely listed as one of the features. You might check the v1.0 schematics (see the RepRap wiki page) to see if you can get more detail from that, my quick look shows J2 in the USB TTL section with pin one as Vcc, Pin 2 is Gnd, Pin 3 is RX and Pin 4 is TX. Also, consider sending a message direct to Panucatt. They are willing to help, but slow on responses sometimes.

[flickerfly]

I just realized, I was wrong about the J2 location. It's actually just to the right of the Atmega chip above the D4 breakout area. It just jumped out at me on the wiring diagram. Not sure how I didn't see it earlier.

[fma]

I got an answer from panucatt. The TX/RX pins on J2 connector are the same connected on internal usb chip.

I'm waiting for informations how to improve stability (noise immunity) by change a few components. I'll let you know when I have news.

[fma]

Here are the mods suggested by Roy:

So basically I used SMT ferrite beads on the data line of the USB. This worked on my desk but may have different results with yours since you might have more noise and spikes on your power lines. I also placed another SMT Ferrite bead from the USB connetor chassis going to ground. The newer X3 has an open pad for this but if you have the older version just scrape the solder mask near one of the usb connectors 4 legs to older the part. See attached.

Here are the part numbers I used. Anything similar should be fine.

For the Data lines, CIC21J221NE:

http://www.digikey.com/product-detail/e ... erprise=44

For the USB chassis - CIS21P300NE:

http://www.digikey.com/product-detail/e ... ND/3973705

Again your results may vary, Also make sure that your main printer power supply has clean power and is not over driven, these are the main sources of noise.

I didn't tried it yet, as I'm now using pure serial connection. See next post.

[fma]

As said, I didn't try Roy's mod, as I have to order the needed parts.

But I tried a pure serial connection, using a RS232-TTL converter connected to the J2 connector, and it works great! I can now switch on/off any device on the same power line (soldering iron, vacuum pump, monitor...) without any problem

For now, I'm powering up the RS232-TTL convertor from an external power supply (9V), as this convertor has an internal 5V supply regulator. The 5V line is also used to power up the printer, through J2 connector. I totally removed the jumper which select the power (INT / USB); this way, nothing can happen.

Another solution is to let the jumper on INT position, and use J2 5V output to power up the RS232-TTL converter. But mine can't be powered-up this way; I would need to remove the voltage regulator. The other issue is you can't switch on the main printer power from Repetier.

Third solution is to use a USB cable without data lines only to power up the printer and the converter (putting the jumper on the USB side).

Last solution would be to use RS232 RTS line, but I do'nt now if I can drain enough power.

[flickerfly]

All that talk of power reminds me that I've been thinking about using the Azteeg to turn on and off the PC power supply. I know it can be done on a modified ATX supply, but I'm not sure where to plug things into the Azteeg. I assume I need to power the basics from the USB or RS232-TTL like you mentioned or maybe use the standby power from the modified ATX supply.

Has anyone explored this more than me?

[fma]

That's my next move!

Yes, need to power as you said, and I think we just need connect the PS-On line of the power supply to the ATX POWER pin on X3:

http://reprap.org/mediawiki/images/a/a5 ... iagram.jpg

Could someone confirm?

[fma]

Ok, I did that, and it works fine!