Component: RFID (MFRC522) (Wireless)
| Author | Ben Rowland and STibor |
| Version | 3.0 (Release) |
| Category | Wireless |
Contents
RFID (MFRC522) component
Functions designed to work with the MFRC522 contactless reader IC. The MFRC522 supports all variants of the MIFARE Mini, MIFARE 1K, MIFARE 4K, MIFARE Ultralight, MIFARE DESFire EV1 and MIFARE Plus RF identification protocols.
Examples
Here is a basic example program that reads the UID from a Mifare RFID tag and displays on an LCD. If the UID matches the UID stored in memory then a solenoid will fire allowing a door to be unlocked etc.
Here is a basic example program to read and modify data stored on a Mifare RFID tag.
Downloadable macro reference
CompareUID
Compares the UID from the ReadCardSerial macro with 4 byte UID.
Returns 0 if the addresses match.
Parameters
- BYTE Add0
- BYTE Add1
- BYTE Add2
- BYTE Add3
Return value
IsNewCardPresent
Is there a card present for us to communicate with.
Returns 0 for no card and 1 for valid card present.
Parameters
- This macro has no parameters
Return value
GetType
Translates the SAK (Select Acknowledge) to a PICC type
Parameters
- BYTE sak
- The SAK byte returned from PICC_Select
Return value
AntennaOff
Switches off the RFID antenna to save power.
The antenna must be switched on again before communicating with an RFID tag.
Parameters
- This macro has no parameters
Return value
- This call does not return a value
ReadCardSerial
Simple wrapper around PICC_Select.
Returns true if a UID could be read.
Remember to call PICC_IsNewCardPresent(), PICC_RequestA() or PICC_WakeupA() first.
The read UID is available in the class variable uid.
Parameters
- This macro has no parameters
Return value
MifareWrite
Writes to a block of data on a MIFARE type tag
Parameters
- BYTE BlockAddress
- BYTE Buffer
- BYTE BufferSize
Return value
Select
No additional information
Parameters
- BYTE ValidBits
Return value
StopCrypto
Used to exit the PCD from its authenticated state.
Remember to call this function after communicating with an authenticated PICC - otherwise no new communications can start.
Parameters
- This macro has no parameters
Return value
- This call does not return a value
MifareRead
Reads from a block of data on a MIFARE type tag
Parameters
- BYTE BlockAddress
- BYTE Buffer
- BYTE BufferSize
Return value
Authenticate
This command manages MIFARE authentication to enable a secure communication to any MIFARE Mini, MIFARE 1K and MIFARE 4K card.
All keys are set to FFFFFFFFFFFFh at chip delivery.
The authentication is described in the MFRC522 datasheet section 10.3.1.9.
Parameters
- BYTE Command
- PICC_CMD_MF_AUTH_KEY_A or PICC_CMD_MF_AUTH_KEY_B
- BYTE BlockAddress
- The block number
- BYTE Key
- Crypteo key to use
Return value
HaltA
Instructs a PICC in state ACTIVE(*) to go to state HALT
Parameters
- This macro has no parameters
Return value
ReadUIDByte
No additional information
Parameters
- BYTE Index
- 0-9 = UID Data Bytes, 10 = UID Length, 11 = UID SAK
Return value
AntennaOn
Switches on the RFID antenna.
Called as part of the Initialise macro.
Parameters
- This macro has no parameters
Return value
- This call does not return a value
Initialise
Initialises the RFID module ready for interaction with RFID tags.
Parameters
- This macro has no parameters
Return value
- This call does not return a value
Simulation macro reference
This component does not contain any simulation macros
Property reference
Channel
This property is of type Fixed list of ints and can be referenced with the variable name cal_spi::CHANNEL.
SPI Channel selector
Prescale
This property is of type Fixed list of ints and can be referenced with the variable name cal_spi::PR_SCALE.
Prescale option selector
MOSI
This property is of type Single digital pin and can be referenced with the variable name cal_spi::MOSI.
SPI Data Out Pin SDO - Also Known as Master Out Slave In (MOSI) when used in Master mode.
MISO
This property is of type Single digital pin and can be referenced with the variable name cal_spi::MISO.
SPI Data In Pin SDI - Also Known as Master In Slave Out (MISO) when used in Master mode.
CLK
This property is of type Single digital pin and can be referenced with the variable name cal_spi::CLK.
SPI Clock Pin CLK - The Clock signal is driven by the SPI master.
CS / SS
This property is of type Single digital pin and can be referenced with the variable name cal_spi::SS.
Chip Select / Slave Select Pin
Master Mode: General purpose output pin used to select the remote SPI device.
Slave Mode: Hardware chip select pin input used to select the SPI device.
Reset
This property is of type Single digital pin and can be referenced with the variable name reset.
MFRC522 Reset Pin
Label
This property is of type Line of text and can be referenced with the variable name label.
No additional information
Scope Traces
This property is of type True or false and can be referenced with the variable name cal_spi::ScopeTraces.
Selects if the scope traces are automatically generated or not
Console Data
This property is of type True or false and can be referenced with the variable name cal_spi::ConsoleData.
Selects if the console data is automatically generated or not
Injector
This property is of type Fixed list of ints and can be referenced with the variable name cal_spi::Injector.
No additional information
