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7

I have found a solution although I take no credit for it: "Turns out the Raspberry Pi 3 uses the first serial port for its integrated Bluetooth! There are several ways to get around the problem, knowing this. For now and for my purposes, simply disabling bluetooth did the trick: add dtoverlay=pi3-disable-bt to /boot/config.txt and then sudo systemctl ...


4

I finally figured it out. What happened was that when I first got the modules I accidentally hooked them both up to a 5V rail instead of the recommended 3.3V, or at least this is my best guess as to why nothing was working. I got another pair of the RF modules today and made sure to only connect them to 3.3V and they work absolutely perfectly with all of the ...


3

Make sure the SPI Interface is enabled: Edit the file /boot/config.txt and add the following two lines: device_tree_param=spi=on dtoverlay=spi-bcm2708 Reboot the Pi and check if the SPI Interface software is running: $ dmesg | grep spi You should see something like: [ 8.577659] bcm2708_spi 20204000.spi: master is unqueued, this is deprecated [ 8....


3

Enable SPI by adding the line dtparam=spi=on to /boot/config.txt. This will enable the main SPI device (two slave selects). crw-rw---- 1 root spi 153, 0 Oct 18 21:01 /dev/spidev0.0 crw-rw---- 1 root spi 153, 1 Oct 18 21:01 /dev/spidev0.1 To also enable the auxiliary SPI device (three slave selects) add the line dtoverlay=spi1-3cs to /boot/config.txt. crw-...


3

The PN532 has multiple interfaces and can do a lot more than just "read" a card. So it implements a serial protocol that requires you send it commands asking it to do something and give you a response. That's why you're getting no data, because you're not sending it a command to configure for reading and asking it to tell you the card it can see (if any). ...


3

As joan pointed out in the comments above, there were extra spaces after "Keycard"


2

Looks like the pins are not soldered in


2

One of the good points about Python is that you can use it interactively. From a command prompt type python. Then try out the commands. import serial import time device = serial.Serial("/dev/ttyUSB0", 2400) while True: print(device.read(12)) # important to indent this line time.sleep(1) # important to indent this line # press return here to ...


2

Okay, I had a go at this using my ACR1251U-A1, which is pretty similar to your model, and I got it working. First a short explanation, as far as I could understand the problem: the data that you were trying to send is not a complete, valid USB message; it is only the payload to be delivered to the reader. pyusb, libusb etc. seem to expect you to be fluent in ...


2

It is possible to use a RPi as a "desktop" in the case that you describe, so long as the manufacturer of the UHF RFID (or, for that matter, any other USB) device provides: a driver pre-compiled for the OS that you are using (i.e. (in all probability) a Linux variant, unless you use Windows 10 IoT) and; the driver has been compiled for ARM (the processor ...


2

Actually you are right. They have change the peripheral addresses in raspberry 3 kernel which uses the bcm2835. There is a comment in the forums in the link below about that. Check saadnasir comment https://www.raspberrypi.org/forums/viewtopic.php?f=32&t=75003 There is also this http://www.instructables.com/id/Raspberry-Pi-3-Model-B-MIFARE-RC522-RFID-...


2

This project on hackster.io outlines what appears to be a successful approach using a Cottonwood: Long Range UHF RFID reader with a Raspberry Pi 2 running Windows IoT. Per previous comments it's fairly expensive at $187 per unit - some googling suggests that that's going to be an unavoidable cost for this type of unit. The reader's specs list the effective ...


2

I have no rep, so can't comment directly on Patrick's reply. I know this post is old, but nearly no NFC work has been done for Python. There's one module out there that only does SPI, and there's the libnfc library. I've managed to get I2C working by simply running a subprocess. it's slow, and I'm working to improve that, but here it is. (Assuming you have ...


2

I ran into the same Problem... You got to use virtual-env (recommended by community). Did you import SPI in your script? Else: Reinstalling all the dependencies inlcuding the SPI Module in an active virtual-environment did the trick for me. The Doc´s: Virtualenv.


2

I had exactly the same problem problem: communication with host is OK, but tags are not detected. I believe that this is a fake Elechouse module, and it can't work because of terribly designed RF part. To fix it, I replaced all the components near the antenna as follows: L0 = 680nH; C0 = 180pF; C1 = 22pF; C2 = 168pF (100 pF and 68 pF in parallel); R2 = 3.9 ...


2

In your loop you're reading twice from the serial port: read_serial=ser.readline() s[0] = str(ser.readline()) which is probably not what you're trying to intend here. It reads more from the serial port and hiding it from the user. It should probably look more like this (though I have to admit that I am not sure where you're going with this s[0] and s = [0] ...


2

If I remember correctly the PN532 device is supported by libnfc via the UART. It might be simplest to use the UART solution as it's more likely to be usable out-of-the-box. The UART connection requires four connections: Pi ground - PN532 ground Pi 3V3 - PN532 5V Pi TX - PN532 RX Pi RX - PN532 TX Note that by default the board appears to be jumpered for ...


2

Considering the info available on the link you provided, I would use the RS232 port of the RFID reader. If the RFID device has real RS232, you need a voltage level translator between the standard RS232 voltages and the Raspberry 3.3V GPIO, like this one: https://www.sparkfun.com/products/11189 RS232 level translation is explained in this article (here they ...


2

The right way to do it would be getting pam_nfc module working with your RFID reader. Once installed, you'll have this pam-nfc-add command which can associate a user with a tag. Another way is to write your own my_getty command which supports the reader, and refer to it from /lib/systemd/system/getty@.service instead of the original agetty. When the correct ...


2

The value 1437495737 is in hex 55ae71b9, or in little endian notation b9 71 ae 55 while the integers 185 113 174 85 are in hex also b9 71 ae 55. So you get the same value, just in different representation.


1

There appear to be 14 characters not 15. The datasheet says there should be 16 but the CR and LF do not appear to be present. So try reading 14 rather than 15 characters. EOT and SOT are ASCII characters with the values 2 and 3. Look at an ASCII chart to get the idea. They are distinct from the stop bit. Each ASCII character is sent as 8N1 (as defined ...


1

I'm looking at the same problem with (currently) a single but different RFID USB (HIDevice) reader. It presents a 10-digit number and a (CR +?) LF (from the tag read) as if it was typed in at a keyboard. I made some headway with adding a new rule 10-local.rules to the /lib/udev/rules.d/ system to add a known name as a symlink in the /dev directory: ACTION!...


1

I have the linked housing and your setup will not fit in there, but I guess you're asking for housings in general and not the particular one. Next, I think you want to know what the impact of the additional plastic is on the wireless signal. For the housing, you could design a 3D model and then have it printed. That way it will fit exactly to what you have ...


1

Modmypi makes a case which accepts spacer plates that raise the height of the case. You would need to mount the RFID reader to the cover (hot glue and/or some standoffs would work) but it should fit given the right number of spacer plates. One additional add on for this case is a cover for the SD card which is tamperproof. Another option would be to create ...


1

To resolve this issue, edit in your MFRC522 library a line of spidev code for 1.0. Add dtoverlay = spi1-3cs to the /boot/config.txt file. Edit or reduce reader 22 reset to any other GPIO in the MFRC522 library.


1

I always use dtparam=spi=on. Remove the dtoverlay line, it is not needed. By default the new spi-bcm2853 module should be loaded.


1

This sounds like an excellent application for RFID cards. RFID scanners are very cheap. When an RFID card or key fob is brought into proximity of the scanner, the scanner will record/register its arrival. Each RFID card can have its own unique ID and can also be programmed to contain a small amount of additional information. The most popular RFID scanner ...


1

I just had a look at some Amazon reviews (hopefully of the item you have). The reviews suggest it does not have a full SDK. It just acts as a keyboard and prints out the card number (plus carriage return). One reviewer noted that the DIP switches change the data format as follows. So I have a card with the UID 4B32EcDE (32bit Dec 3740021323) in the ...


1

Your rc522 reader has "CS" pin which can be controlled to activate each rc522 reader. You can try to toggle them one by one to be able to read the individual one. The MFRC522-python module does not seem to allow to control/specify it, so you may need to modify the module or control GPIO pin yourself: that's line 113 in https://github.com/mxgxw/MFRC522-...


1

You mentioned that this is a compiled application, that works on x86 processors. This sounds like your problem. The Raspberry Pi's processor doesn't use an x86 architecture, or anything close to it. Rather, the RPi 2 uses an arm7 instruction set. To get it to work on the RPi, you will have to recompile it targeting the RPi's architecture at the very least. ...


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