Hello, I am new to Arduino. I am trying to create a reader that can read my cat's chip. I bought this sensor on Amazon here(LINK). I tried to configure it, but I am not receiving any data from the RX serial port. I am concerned that the sensor might be malfunctioning. Can you help me? Thank you very much.
I decided to use the 9V battery to the power supply for the RFID sensor.
this is my wire connection:
Positive of the 9V battery to the 5V-9V input of the sensor Negative of the battery to the negative of the sensor and to the ground of the Arduino Uno TX of the RFID sensor to the D2 (RX) pin of the Arduino Uno
What output, if any, do you see in the Serial monitor?
Do you have access to a multimeter for testing?
Did your module come with a sample RFID tag, for testing?
Does anything change when you attempt to scan a tag? I believe it is common for these modules to only output serial data when a tag is detected.
If the Uno is only being used to transfer the RFID module's output to the computer, there is an easier way than using SoftwareSerial.
If you flash a blank sketch to your Uno, you should be able to connect the module's tx pin to Uno's RX pin (Pin 0). The serial data will pass through to the computer just fine.
The module's information page suggests that the current draw is about 60mA (if powered by 6V). Even at 9V, I suspect the module's current draw might be a bit high for that 9V battery.
The information page suggests that a 5V power supply is acceptable. In theory, you should be able to completely disconnect the 9V battery, and power the module directly from the Arduino's 5V pin, for testing.
It would be nice to confirm the current draw first using a multimeter, incase there is some hardware fault, but if you are brave you can probably just connect it up..
The whole "wires taped / wrapped together" thing is not ideal, but hopefully it isn't the source of your issues.
In the next few hours, I will try using a multimeter to check the presence and operation of the sensor. However, just to be safe, I have decided to order a new sensor, which will arrive in a couple of days, to verify its functionality. The important thing for me was to understand if the circuit could work well as shown in the photos.
I decided to use a 9V battery because I need a wider detection range.
That's a valid reason. I was only really suggesting trying a different power source as a test.
I could be missing something, but I can't see any glaring problems there. I'm not completely confident in the twist together wire joins, but I doubt it's the key issue.
If you do decide to order a new module, it will certainly help eliminate hardware failure as an issue.
If your module didn't come with a tag for testing, it would be good to get one at the same time, for testing. The larger "cattle ear tag" types will give you better reception for testing, compared to the, smaller implantable type. Make sure that is the ISO11784/85 FDX-B type.
i have a tag for testing and there is a small chip like a
I received the new sensor, and I immediately tried to configure it. The connections are the same as shown in the photo, but it still doesn't work. When measuring with a multimeter, I have 8.45V at the positive and negative terminals, and around 4V at the output of the two antenna pins. I still don't understand what I could be doing wrong.
It's quite late here so just a quick thought: the coil is made of enamelled copper wire. I'm not sure whether this is something you are aware of or not, but in order to connect to the ends of the coil, you will probably need to use sandpaper to remove the enamel coating and expose bare metal. Is this something you did before twisting the wires together? (Soldering the coil directly to the board would also be better)
Perhaps you can use your multimeter's continuity test mode to check if the ends of your coil are exposed copper, able to make a good contact? You will need to disconnect the coil from the board to make this test.
Thank you so much indeed, the problem was indeed the insulating varnish applied on the antenna. Unfortunately, being a novice in electronics, I was not aware of this. I thank you very much, I will need to study more!
One last question, if I wanted to increase the range, should I create a larger solenoid, maybe with more turns?
Maybe.. but designing antennas is a difficult task; it is beyond me!
Without redesigning the loop antenna, you can maybe increase the range a bit by making a very good quality connection from the board to the loop. There are waves of electricity going through the loop, and if there is some obstacle for the wave to pass (like two wires joining), it can cause the same problem as an ocean wave trying to fit through a small gap: lots of ripples.
As far as I know, this circuit uses a combination of the loop, and capacitors, so that the waves in the loop antenna can resonate. Maybe you can think of this a bit like a guitar string: it needs to be the right length and tension so that you can get the right note.
This part of the manual talks about using solder to open or close J1 - J5. This can add or remove some capacitors, to try tune the "guitar" closer to your ideal "note".
Maybe it is possible that the module is able to deliver more power, and a bigger loop could help. Maybe the module can't deliver more power, but a bigger loop with less turns could possibly get a better reception than the smaller loop with lots of turns (?)
The difficult part is: if you try to make a new loop, it needs to have the same properties as the old loop, otherwise the "guitar string" won't make the right note anymore. The property to measure is "Inductance". I think it would be difficult to experiment with new loops unless you have some special tools: an LCR meter to measure the "Inductance", and an oscilloscope to measure the voltage of the wave in the loop.
Like I mentioned at the beginning of this post, I don't have much knowledge in this area, so don't listen too closely to any of this. I believe that there is a lot of very precise design and math that should really be used in this situation.
