I currently have an actuator with a controller. The controller receives UP/DOWN from a small keypad that connects in using an Ethernet cable. However, for the project I'm working on, the actuator is upside-down so from a UX perspective this would be confusing for a user (UP is making the actuator move an object DOWN).
What I would like to do instead of hacking the Ethernet cable is to use an Uno to swap the signals. This being, an Ethernet shield would handle the incoming data, the Ardunio would be programmed to 'flip' the signal wires digitally, then send the new data out from another shield. This would make UP appear to be up and DOWN appear as down. As well, I could later add sensors to add some automation to this process down the road (icing on the cake).
Is this possible?
Here is a data sheet of the actuator controller I have:
I’d alter the wiring in the key pad to suit, this type of solution seems the best approach .
As you sure the actuator uses Ethernet for controlling ? Seems unlikely looking at the data sheet , which list other protocols and even give Arduino example codes .
You need to be more specific about what you have and work out what the controller is doing , or build a new one around the Arduino using their code
Manufacturer send me the data sheet on the key pad/controller pin outs for RJ45 connection. Pins 7 and 8 on the cable head control the up and down motion. Cutting the connector off and reordering the wiring is one solution, but won't allow me to add automated features down the road. So I'm looking at getting 2 of these: https://store.arduino.cc/usa/arduino-ethernet-shield-2
One would receive and one would transmit. Now just need to find information on the code structure (this won't be an IoT device?).
Just because they use an RJ45 connector does not make it any sort of ethernet or IoT device. I very seriously doubt you need those ethernet shields.
Does that datasheet say anything about the signals? It could just be a simple HIGH/LOW signal. You will need to find out before you start building a solution.
Attached the datasheet they sent. It's sparse, but does look like a shield won't not be needed. That said, the supplier could not give me any info about the other pins on the cable due to patent they have on the control box...
The Key Pad does have other functions that those wires are probably attached to, so I guess just setup a wiring scheme where only Pin 7/8 go to the Uno and the others direct to the control box.
So pins 7 and 8 are open collector. If they are shorted to ground, they activate. If you insert an arduino in the middle, you read pin 7 and 8 but set the outputs for 8 and 7 downstream.
It doesn't really give you any more functionality than swapping the wires.
If you don't know what the other signals are, it will be difficult to "extend" to anything else.
otter:
That said, the supplier could not give me any info about the other pins on the cable due to patent they have on the control box...
If you know something about the manufacturer, you can sometimes find the patent portfolio on Google patents. Maybe there is some information given away there.
blh64:
It doesn't really give you any more functionality than swapping the wires.
That should be ok. The future automation is connecting BLE to the Arduino to allow remote controlling up and down movement on an android device. Their key pad does things like error messages and saved elevation states, which aren't needed for the results I'm looking for. You can still use them, but won't be dependent on the wire swap.
I'll have to check to see what data pins 7/8 on the cable are sending. I assume it will be analog.
otter:
That should be ok. The future automation is connecting BLE to the Arduino to allow remote controlling up and down movement on an android device. Their key pad does things like error messages and saved elevation states, which aren't needed for the results I'm looking for. You can still use them, but won't be dependent on the wire swap.
I'll have to check to see what data pins 7/8 on the cable are sending. I assume it will be analog.
I would not assume that. If shorting a pin activates it, the keypad is acting like a simple push button. Unpushed, it goes high through a pull-up resistor somewhere. Pushed, it shorts to ground. You will want to check what voltage levels are on that pin before connecting it to an arduino.
blh64:
You will want to check what voltage levels are on that pin before connecting it to an arduino.
With an ethernet cable (~48V but will do a check for amount at different running states), I'm assuming I'd need a setup with a voltage divider on the pin going into the Uno and transistor from connecting pin 7 to 8 (and another vice versa) and a base pin on the Uno....
Sounds silly, but say if the BLE is added...hmm but then the pins aren't shorting since the BLE is on the Uno and not the keypad that's completing the circuit...the Uno is only reading the connected circuit at this point, so I'd have to tie in the ground somehow to allow the current to bypass the keypad? ...This is if you want to automate it so the Uno can be programmed with its own up/down sequence that is independent of the keypad.
Just because you are using a CAT5 cable, does not indicate anything at all about Ethernet or whatever. They are a very useful cable for simple 5V lines, I2C lines, etc. You seem to be hung up on the fact that because the interface has an RJ45 connector and uses CAT5. Twisted pair cables are handy and cables commonly used for ethernet (CAT5, CAT6, etc.) are very ubiquitous and cheap.
