RFID and NFC on a Budget

Hello all!

I am interested in experimenting with NFC and or RFID for some projects, but I don't know what range to look for.

I know that I want to be able to both READ and WRITE to some blank tags, cards, etc. I know that I want to be able to use the cards with my phone's integrated RFID and or NFC (I own a Samsung Galaxy S5, but I am assuming most smartphones use the same range) I know that I want the ability to read data from a reasonable range, it should ideally work indoors at about 12 inches.

I need a read and write module of the specific range type, I need some cards that I can read and write to, and some tags. Do I need anything on my phone to enable the NFC? If I use cards that can only be read, what will already be on the card? Is there a specific brand, kit, or product that you recommend for my needs?

Thanks in advance.

I forgot to mention, I would like to be able to tap the reader, as well as have a card in my pocket and read it from about 12 inches away. I will be using it to store information that will let you into a room or will allow you to make changes to the whole automation system that it will be integrated into. Maybe also basic information about a person like name? Or, information about what key set is in the drawer when a tag is on a key chain.

Thanks again! I look forward to learning, so please let me know WHY you suggest anything you do.

I know that I want the ability to read data from a reasonable range, it should ideally work indoors at about 12 inches.

While that range is possible with 125KHz cards if you design your own reader, it is not realistic for the smart cards that are used on phones. Also these 125KHz cards do not store data just an ID number.

You can't get the range because they use all in one ICs and you get too much noise from the digital side of the circuit.

Maybe also basic information about a person like name?

Why do you need that? If it is required then the correlation between an ID number and the name can be made in the data base that you use to determine if access is permitted.

If I use cards that can only be read, what will already be on the card?

A unique ID number, 64 or 128 bits long.

Is there a specific brand, kit, or product that you recommend for my needs?

I don't think you will find anything. Reasoning - worked in RFID design for 5 years as the embedded systems manager.

Grumpy_Mike: While that range is possible with 125KHz cards if you design your own reader, it is not realistic for the smart cards that are used on phones. Also these 125KHz cards do not store data just an ID number.

You can't get the range because they use all in one ICs and you get too much noise from the digital side of the circuit. Why do you need that? If it is required then the correlation between an ID number and the name can be made in the data base that you use to determine if access is permitted. A unique ID number, 64 or 128 bits long. I don't think you will find anything. Reasoning - worked in RFID design for 5 years as the embedded systems manager.

Thanks for the reply!

Using what is in the phones, would you be able to store more data in it? Thanks

would you be able to store more data in it?

More that what? These cards tend to be Mifair cards. You can get them in half K, 1K and 4K versions.

tyler_newcomb: I know that I want the ability to read data from a reasonable range, it should ideally work indoors at about 12 inches.

The only RFID I know that can read more than 15cm, actually for couple of meters (between 3m up to 15m) are those that operates in UHF band.

Keep in mind that NFC is a different technology of almost RFID out there, so what's the difference ? Short Answer: RFID is the process by which items are uniquely identified using radio waves, and NFC is a specialized subset within the family of RFID technology. Specifically, NFC is a branch of High-Frequency (HF) RFID, and both operate at the 13.56 MHz frequency. NFC is designed to be a secure form of data exchange, and an NFC device is capable of being both an NFC reader and an NFC tag. This unique feature allows NFC devices to communicate peer-to-peer.

BUMP

I am still looking for what items I would need to do the desired project. Again, I want to be able to use it to unlock a door or a cabinet and store that data of WHO does it.

Do I need a read AND write module?
Do I just need a read module?
Is there any brand, model, or type you would recommend for either?
Will a database of 3 cards with info such as name associated with it require an SD card sheild to hold all the data?

Thanks again.

Provided your phone can programme the cards you only need a reader for unlocking. If you use a database you do not need to programme for unlocking them just read the uid.

Reader writer shields are available from addafruit for NFC cards but are more expensive than those available for RFID read write.

RFID cards such as mifare can store kilobytes of data.

NFC tags are limited to a hundred bytes or so.

tyler_newcomb: BUMP

Do I need a read AND write module? Do I just need a read module? For a simple unlock device you just need a read module.

Is there any brand, model, or type you would recommend for either?

https://www.adafruit.com/product/789

There are much cheaper cards for 4 or so on ebay which will do the job using mifare (not NFC cards) but be aware that although there are support libraries available , programming NFC readers is not a beginner project.

Will a database of 3 cards with info such as name associated with it require an SD card sheild to hold all the data?

You will need some sort of non volatile memory to store the access records to retrieve later unless there is a wired connection.

Be aware that rfid readers consume a fair bit of power so if you use battery power an on off button will be needed before the tag is presented.

Boardburner2: Provided your phone can programme the cards you only need a reader for unlocking. If you use a database you do not need to programme for unlocking them just read the uid.

Reader writer shields are available from addafruit for NFC cards but are more expensive than those available for RFID read write.

RFID cards such as mifare can store kilobytes of data.

NFC tags are limited to a hundred bytes or so.

Thank you. So, from what I understand, 13.56MHz RFID is the better option because it has the ability to hold more data? I thought NFC was just another name for the 13.56MHz range of RFID? Also, the kit you linked me to says that it has a "low power mode" would this eliminate the need for a switch as well? Thanks

So, from what I understand, 13.56MHz RFID is the better option because it has the ability to hold more data?

Yes but as you have been told you do not need to have data for your application. The unique ID can match up a name on the data base. There is no advantage in storing a name in the card. Note you will still not get the range you want.

Grumpy_Mike: Yes but as you have been told you do not need to have data for your application. The unique ID can match up a name on the data base. There is no advantage in storing a name in the card. Note you will still not get the range you want.

I realize that you can do it without storing the data, but I would like that ability for future projects such as non-networked unlcok devices with the same tag. The range is actually not an issue, as I have come to realize. I would like a longer range, but the price point is ridiculous for such capabilities.

No.

NFC is a specific protocol which is a subset of 13 MHz RFID in general.

NFC was designed specifically for a purpose, mobile phone and secure payment applications.

13 MHz frequency has been used for some time for RFID, mostly access control.

Also used by the OYSTER card system for payment using encrypted mifare cards.

There is a UHF frequency of 800 MHz or so also used for inventory management/logistics also which has a much longer read range.

Earlier systems using 125 KHz can also have longer range, used for access control ,with large aerials to give range can be used for herd management or car access type things.

Also used for security tags in supermarkets.

tyler_newcomb: Also, the kit you linked me to says that it has a "low power mode" would this eliminate the need for a switch as well?

Unlikely , the arduino itself will draw considerable power unless put into sleep mode as well.

Cross post also i was replying to a previous message before Mike.

tyler_newcomb: I realize that you can do it without storing the data, but I would like that ability for future projects such as non-networked unlcok devices with the same tag.

Even a non-networked system needs a database of numbers that are permitted to open the door, so you are not gaining much carrying data. Where it would be useful is if you wanted to limit access to a number of times in a given period on a non-networked system.

Grumpy_Mike: Even a non-networked system needs a database of numbers that are permitted to open the door, so you are not gaining much carrying data. Where it would be useful is if you wanted to limit access to a number of times in a given period on a non-networked system.

Listen to Mr. Grumpy_Mike, he's correct ! I have build my own access control system, and I use a ethernet shield that support SD-cards, so I use the SD-Cards to store and log all the access, and the Ethernet shield, for a TCP client connection where I can update and upload (manage) all the access on the device! And for my project, I'm using 4 Wiegand 26 bit readers with keypad, also support 34/36 bits and other formats as well!