@MakerJim requested I start a new thread so here it is.
Jim here is my config.yaml
config.zip (1.6 KB)
You will see that the RS485 stuff is currently commented out. I broke the cable a few weeks ago and just took it out to keep running and make parts for the original beta, and just haven’t had time to fix it yet. But it was all working exactly how you see it in the config.
If you need anything else just let me know! Thank you for the help with this!
Indeed, I do see that.
I also see that there’s still a chance you may be in luck.
Here’s how I think we might be able to make this work: We will need to pick off some GPIOs from the top of the RS-485 expansion connector, assign those GPIO pins to UART1, and then map the FluidDial to UART1.
Next step for me is to go look again at Bart’s RS-485 board design. The key to making it work will be how your setup uses (or doesn’t use) RTS. Best case is we can live without. Next best option would be needing to white wire one of the other GPIOs to let that be RTS. That starts getting messy.
If we do this, the ugly way will be to solder some wires to the GPIO that the spindle add on module isn’t using.
No guarantees, but we’ll give this a shot.
I do like the sound of that!
I have both of his boards. When I originally started using it he didn’t have one out that was Isolated. So if one will work and one wont, I do have both options available.
I thought we were already using UART1 for something?? Maybe I am just misunderstanding. That’s very possible lol
None at all expected. And I do greatly appreciate the help!
UART0: Used for boot/firmware load control. Also, after boot, this is used to configure and monitor the TMC2209s.
UART1: Not used in your config
UART2: Defined as the VFD in your config. Defined as a pendant in many other folks’ configs.
Some discussion:
The Bart boards use RTS as a directional control that tells the RS-485 transceiver whether to transmit data or receive.
All well and good, except that needs a GPIO and the expansion connector on a Jackpot only brings over 4 GPIO signals. So, the RS-485 module needs 3, and the pendant needs 2. One too many without doing some fancy hackery.
There are RS-485 transceivers that don’t need the enable, but I’m not sure if FluidNC would be happy about that. I suspect for a point-to-point (FluidNC to Spindle, no other devices), it would be fine. There’s even a transceiver in the same exact part family which works that way. It has a part number a digit off. Sadly, the pinout is different between the two parts (!!).
Not out of luck yet.
Two things we could do:
+. We could try to substitute the RS-485 driver that doesn’t need directional enables. This would let us use the available GPIOs on the Jackpot expansion connector as UART1 and UART2. It would mean either I dead bug a Bart module, wire up a proto board, or spin a new PCB module. Doable as a test.
+. We could pick off a GPIO from one of the MOSFET drivers and use that to run the RTS for the RS-485 module. This would again require some wire routing gymnastics. Still doable.
I’ve been debating making my own module for a pendant. I was going to make one that uses my RJ45 pinout but stopped when Bart released his. Maybe I make myself a module that has spindle and pendant outputs, and has a provision to pick off a GPIO from elsewhere on the host board.
Long winded, late night rambling stream of conscious 
Bottom line: Still looks possible.
Aren’t there 2 of those? If so could we just use those 2 for RX/TX? I don’t use either for anything currently and have no plans of adding anything else. I am guessing no since you didn’t already suggest that but wanted to ask and be clear lol.
No worries at all! I am not in a huge rush for this by any means. I only have a few more days before I head back to work and no time to even mess with it before then. So please don’t feel like you have to rush to figure this out! And again thank you!!
Those are routed to the MOSFETs. We can potentially use the upstream GPIO, but we’d need to cut a trace.
I wonder if @vicious1 keeps a feature request list for Jackpot revisions. If we just had a zero ohm resistor in line to each GPIO controlling a MOSFET, we could do this type of thing. In that scenario, the GPIO would go to both the expansion connector and the MOSFETs. To do this hackery, we’d cut one or both of the zero ohm resistors.
With those two GPIOs available to route over to an expansion connector board, we could make a combo spindle and pendant board. That’s not needed on a 6-pack because it has multiple expansion connectors. But it would be sweet on a jackpot to have both a spindle and pendant interface availbable.
I saw that. And actually was thinking I was going to have to go that direction. But wanted to ask here first before I spent money I didn’t need to. Got enough in all of this stuff already 
Check this out. The GPIOs that go to the MOSFETs run right along side the pins in the expansion connector. It would be so easy to make a mod this way.
Edit:
How to make Jackpot be able to use the MOSFET GPIOs optionally on the expansion connector (from factory, not my hackery…)
Spent more time looking at this today.
I think we can take the isolated RS-485 module and modify it to drive a FluidDial pendant as well as operating the spindle. (It doesn’t use the RTS pin to flip the driver direction!)
I’m going to order one of these to play with.
@MakerJim you are a genius!
That’s awesome news!!!
Be careful. That might lead you to want to try a spindle and see how much quieter it is
I have a copy of Bart’s Isolated RS485 spindle module on its’ way to me.
I also have one of Bart’s FluidDial module PCBs with the RJ12 on it in the same shipment.
@Jonathjon - If I get the modified RS485 module working the way I propose to, I’ll be able to test the pendant, but as you note I don’t have the spindle. 
If I get there, I’ll send it to you to test with your spindle setup. Maybe we can barter a set of XY plates for LR4 RC3 (or release).
At any rate it looks like I’ll have that module in about a week.
That wont be an issue at all!
I just got the call, so I will be leaving tomorrow at 9am CDT to head back to work, crew changing early with the in coming hurricane.
Stay safe!
I rode through a “wimpy” Cat 1 down near Boca Raton 20 years ago, on Land.
Not something I plan to ever repeat!
I should have my testing complete by the time you roll off duty; hopefully able to send a test board along by then.
Oh I’m not worried. Boat can handle more than enough, and if the water starts coming up I just jack up more lol. My relief brought the boat into Port Fourchon this morning so we are in safe harbor. We will just watch it rain and play on our phones LOL
Awesome! Sounds great!
My order of RS-485 spindle adapter and Bart’s FluidDial adapter arrived.
I had intended to also grab some proto modules, but they were out of stock.
So, I ordered a batch of 50 proto adapters from JLPCB as it was essentially no cost difference from ording 2 to ordering 50 when shipping was taken into consideration.
I’ll have plenty of ability to try my crazy ideas for expansion modules for Jackpot.
I plan to get back in the garage this weekend and get machines moving.
I’ll report how testing my crazy idea for an dual pendant/spindle mashup works.
Edit: Next steps for me will be converting two of my existing FluidDial pendants to use the Bart pinout and RJ12 connector.
Once I have that working, then I’ll modify the spindle board to add my crazy idea ending in an RJ12.
I’ll then plug the RJ12 cable and pendant in.
If that works, then I will have to send it on as I don’t have a spindle to test with.
That is so awesome @MakerJim!! Thank you for taking this project on! I can’t wait to see if it actually works!!!
I hope to be cutting a set or 2 of these this afternoon or tomorrow. PM me your address and once I get a set cut I will drop them in the mail to you.
If you still feel like taking a look at those SKR boards I will put them in the package as well. But I’m in no hurry for those.
