I am looking to build a continuity tester using an arduino board. I know that there are some topics already covering this and I have read them. I am looking for some advice regarding the type of board I should use. I havent bought a board yet and I am looking only to use this board for this purpose.
I have a socket (plug) with 58 pins connected to wires, these wires are then all connected to a termination block. I would like to quicken the testing process by creating an automatic tester. From previous topics I gathered that I can get away with using 58 connector pins if I connect the cable ends to LEDs with adjacent pairs in opposite polarity as explained in "https://forum.arduino.cc/index.php?topic=366371.0" answer #10.
This being said, I would like some guidance on the type of board I should buy for this purpose. As I do not know much about Arduino boards it is easy to get lost in the amount of choices one has. I am looking for a very basic board with a screen preferably that has many connector pins.
The LEDs are only there to provide a connection. So lets say we have 3 pins on this cable. Connecting the end side with one LED from pins 1 to 2 and another LED from 3 to 2 (respecting the direction).
Then the Arduino board can test the continuity between 1 and 2 with connection of pin 1 set as an output and connection of pin 2 set as input. This tests both pins 1 and 2 simultaneously and we could program a way to decipher which of the pins is having issues depending on which side is not seeing current/voltage. Then using the program we flip the states of 1 (output) and 2 (input) and test between 3 (output) and 2.
Sorry for the link not working. Its my first post. If you check the previous topic that MarkT helpfully linked (#2) you will see the logistics behind how the tester should work. There is another option of setting input and output fixed pins but then I would need a board with 116 pins which does not seem practical.
Ah, the suggestion was diodes, not light-emitting diodes! LEDs would have a higher voltage drop than ordinary signal diodes (at least 1.8V Vs as little as 0.2V) which might interfere with the intended operation.
Then test between all non-adjacent pairs of leads for shorts (direction not important as there will be at least 2 diodes between them).
I am building a continuity tester for a cable, it has 58 pins. I discussed the workings of this tester in my previous topic: https://forum.arduino.cc/index.php?topic=711849.new#new . However I still did not buy a board. I would like to have some guidance in which board best suits my project before I do so.
Can you explain a bit more about the "cable" that is attached to this 58 pole connector. Are there multiple connectors attached to this "cable" or simply bare ends of wire ?
And what is the current testing procedure.
Some wiring looms can be complex, ruling out a simple 1:1 test, and maybe including joins and embedded components.
You're asking the wrong question. From your cryptic description, any Arduino or ESP board will work. For anyone to give a better reply you need to describe what you are testing. Are you looking for shorts, correct connections? What's on the other end of the wires into the connector?
#9 and #12: The cable has one end that looks like a female plug like the RS232 but much larger with 58 pins in total. The other end is simply loose wires that are connected in a termination box (also 58 connectors). These wires are then connected to a further circuit through that termination box but I only want to test the cable up until that point. Basically I am only testing 58 different wires bundled up together into a plug.
So my idea was to connect a male plug whos wires are connected into an Arduino board and the termination box connected to diodes in a zigzag direction. Then the Arduino board can run its tests. I must insure that each of these wires can conduct current and that when I inject current at pin 1 I can see this current at pin 2. and when I inject current at pin 2 I can see it at pin 3. This is why I do not think every board can work. The full explanation with how I've arrived to this tester is in topic which is linked in #2.
OK. So are you also interested in looking for short circuits or just continuity ? And how much effort is required to prepare the cable end at the termination box before you can conduct a test ?
Yes i believe thats exactly what i need. Digital pins are perfect since i can switch between modes and also use read and write commands easily. Thank you for your help
SteveMann:
Or any Arduino or ESP board with a port expander chip like the MCP20017 port expander.
Thats also a possibility. Since i Have no board yet and will only use it for this purpose I think I will go with the mega but I will keep this in mind if I require customization in the future.
#16 yes i shall be testing shorts as well. All I have to do is send signals from adjacent leads. The termination box is already in place. I am trying to create the hardware and board in such a way where manual belling of all 58 pins would be replaced by a simple plug in of a male cable and some circuitry with diodes in the termination box ( the termination box has holes where some type of connectors can be "plugged" in without removing wires and reconnecting)
