MAXIM MAX66000

19-5528; Rev 0; 1/11
KIT
ATION
EVALU
E
L
B
A
AVAIL
ISO/IEC 14443 Type B-Compliant
64-Bit UID
The MAX66000 combines a 64-bit unique identifier
(UID) and a 13.56MHz RF interface (ISO/IEC 14443
Type B, Parts 2-4) in a single chip. The UID can be
read through the block transmission protocol (ISO/IEC
14443-4), where requests and responses are
exchanged through I-blocks once a device is in the
ACTIVE state. The data rate can be as high as
847.5kbps. The reader must support a frame size of 19
bytes. The device supports an application family identifier (AFI) and a card identifier (CID). AFI and the application data field can be factory programmed with
customer-supplied data. ISO/IEC 14443 functions not
supported are chaining, frame-waiting time extension,
and power indication.
Features
♦ Fully Compliant ISO/IEC 14443 (Parts 2-4) Type B
Interface
♦
♦
♦
♦
13.56MHz ±7kHz Carrier Frequency
64-Bit UID
Supports AFI and CID Function
Write: 10% ASK Modulation at 105.9kbps,
211.9kbps, 423.75kbps, or 847.5kbps
♦ Read: Load Modulation Using BPSK Modulated
Subcarrier at 105.9kbps, 211.9kbps, 423.75kbps,
or 847.5kbps
♦ Powered Entirely Through the RF Field
♦ Operating Temperature: -25°C to +50°C
Applications
Ordering Information
Driver Identification (Fleet Application)
Access Control
Asset Tracking
Mechanical Drawings appear at end of data sheet.
PART
TEMP RANGE
PIN-PACKAGE
MAX66000E-000AA+
-25°C to +50°C
ISO Card
MAX66000K-000AA+
-25°C to +50°C
Key Fob
+Denotes a lead(Pb)-free/RoHS-compliant package.
Typical Operating Circuit
13.56MHz READER
MAGNETIC
COUPLING
MAX66000
TX_OUT
IC LOAD
TRANSMITTER
RX_IN
ANTENNA
SWITCHED
LOAD
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
MAX66000
General Description
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
ABSOLUTE MAXIMUM RATINGS
Maximum Incident Magnetic Field Strength ..........141.5dBµA/m
Operating Temperature Range ...........................-25°C to +50°C
Relative Humidity ..............................................(Water Resistant)
Storage Temperature Range ...............................-25°C to +50°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(TA = -25°C to +50°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
(Note 1)
13.553
13.560
13.567
MHz
At +25°C, MAX66000E
111.0
137.5
At +25°C, MAX66000K
123.5
137.5
RF INTERFACE
Carrier Frequency
fC
Operating Magnetic Field Strength
(Note 1)
Power-Up Time
H
t POR
(Note 2)
dBμA/m
1.0
ms
Note 1: System requirement.
Note 2: Measured from the time at which the incident field is present with strength greater than or equal to H(MIN) to the time at
which the MAX66000’s internal power-on reset signal is deasserted and the device is ready to receive a command frame.
Not characterized or production tested; guaranteed by simulation only.
Detailed Description
The MAX66000 combines a 64-bit UID and a
13.56MHz RF interface (ISO/IEC 14443 Type B, Parts
2-4) in a single chip. The UID can be read through the
ISO/IEC 14443-4 block transmission protocol, where
requests and responses are exchanged through Iblocks once a device is in the ACTIVE state. The reader must support a frame size of at least 19 bytes. The
data rate can be as high as 847.5kbps. The MAX66000
supports AFI and CID. ISO 14443 functions not supported are chaining, frame-waiting time extension, and
power indication. Applications of the MAX66000
include driver identification (fleet application), access
control, and asset tracking.
Overview
Figure 1 shows the relationships between the major
control and memory sections of the MAX66000.
Figure 2 shows the hierarchical structure of the ISO/IEC
14443 Type B-compliant access protocol. The master
must first apply network function commands to put the
MAX66000 into the ACTIVE state to read the UID or
system information. The protocol required for these network function commands is described in the Network
Function Commands section. Once the MAX66000 is in
the ACTIVE state, the master can use the memory function commands. Upon completion of such a command,
2
INTERNALSUPPLY
VOLTAGE
REGULATOR
RF
FRONTEND
ISO 14443
DATA
fc
FRAME
FORMATTING
AND
ERROR
DETECTION
UID, AFI,
APPLICATION
DATA FIELD
MODULATION
Figure 1. Block Diagram
the MAX66000 returns to the ACTIVE state and the
master can issue another memory function command or
deselect the device, which returns it to the HALT state.
The protocol for these commands is described in the
Memory Commands section. All data is read and written least significant bit (LSb) first, starting with the least
significant byte (LSB).
_______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
MAX66000
MAX66000
COMMAND LEVEL:
NETWORK
FUNCTION COMMANDS
MEMORY FUNCTION
COMMANDS
AVAILABLE COMMANDS:
DATA FIELD AFFECTED:
REQUEST (REQB)
WAKEUP (WUPB)
SLOT-MARKER
HALT (HLTB)
SELECT (ATTRIB)
DESELECT (DESELECT)
AFI, ADMINISTRATIVE DATA
AFI, ADMINISTRATIVE DATA
(ADMINISTRATIVE DATA)
PUPI
PUPI, ADMINISTRATIVE DATA
(ADMINISTRATIVE DATA)
GET SYSTEM INFORMATION
GET UID
64-BIT UID, AFI, CONSTANTS
64-BIT UID
Figure 2. Hierarchical Structure of ISO/IEC 14443 Type B Protocol
MSb
LSb
64
57 56
E0h
49 48
45 44
2Bh
0h
37 36
FEATURE CODE (01h)
1
36-BIT IC SERIAL NUMBER
Figure 3. 64-Bit UID
LSb
1
0
START
BIT 1
MSb
BIT 2
BIT 3
BIT 4
BIT 5
BIT 6
BIT 7
BIT 8
STOP
Figure 4. ISO/IEC 14443 Data Character Format
Parasite Power
As a wireless device, the MAX66000 is not connected
to any power source. It gets the energy for operation
from the surrounding RF field, which needs to have a
minimum strength as specified in the Electrical
Characteristics table.
Unique Identification Number (UID)
Each MAX66000 contains a factory-programmed and
locked identification number that is 64 bits long
(Figure 3). The lower 36 bits are the serial number of the
chip. The next 8 bits store the device feature code,
which is 01h. Bits 45 to 48 are 0h. The code in bit locations 49 to 56 identifies the chip manufacturer according
to ISO/IEC 7816-6/AM1. This code is 2Bh for Maxim.
The code in the upper 8 bits is E0h. The UID is read
accessible through the Get UID and Get System
Information commands. The lower 32 bits of the UID are
transmitted in the PUPI field of the ATQB response to
the REQB, WUPB, or SLOT-MARKER command. The
upper 32 bits of the UID are factory programmed into
the application data field, which is transmitted as part of
the ATQB response. This way the master receives the
complete UID in the first response from the slave. See
the Network Function Commands section for details.
ISO/IEC 14443 Type B
Communication Concept
The communication between the master and the
MAX66000 (slave) is based on the exchange of data
packets. The master initiates every transaction; only
one side (master or slaves) transmits information at any
time. Data packets are composed of characters, which
always begin with a START bit and typically end with
one or more STOP bits (Figure 4). The least significant
data bit is transmitted first. Data characters have 8 bits.
Each data packet begins with a start-of-frame (SOF)
character and ends with an end-of-frame (EOF) character. The EOF/SOF characters have 9 all-zero data bits
(Figure 5). The SOF has 2 STOP bits, after which data
characters are transmitted. A data packet with at least
_______________________________________________________________________________________
3
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
STOP/IDLE
1
0
START
BIT 1
BIT 2
BIT 3
BIT 4
BIT 5
BIT 6
BIT 7
BIT 8
BIT 9
Figure 5. ISO/IEC 14443 SOF/EOF Character Format
SOF
ONE OR MORE DATA CHARACTERS
CRC (LSB)
CRC (MSB)
EOF
TIME
Figure 6. ISO/IEC 14443 Frame Format
CARRIER AMPLITUDE
MODULATION INDEX
1
0
1
M = A - B = 0.08 TO 0.14
A+B
1
0
1
A
B
t
Figure 7. Downlink: 8% to 14% Amplitude Modulation
3 bytes between SOF and EOF is called a frame
(Figure 6). The last two data characters of an ISO/IEC
14443 Type B frame are an inverted 16-bit CRC of the
preceding data characters generated according to the
CRC-16-CCITT polynomial. This CRC is transmitted with
the LSB first. For more details on the CRC-16-CCITT,
refer to ISO/IEC 14443-3, Annex B. With network function commands, the command code, parameters, and
response are embedded between SOF and CRC. With
memory function commands, command code, and
parameters are placed into the information field of
I-blocks (see the Block Types section), which in turn
are embedded between SOF and EOF.
4
For transmission, the frame information is modulated on a
carrier frequency, which is 13.56MHz for ISO/IEC 14443.
The subsequent paragraphs are a concise description
of the required modulation and coding. For full details
including SOF/EOF and subcarrier on/off timing, refer to
ISO/IEC 14443-3, Sections 7.1 and 7.2.
The path from master to slave uses amplitude modulation with a modulation index between 8% and 14%
(Figure 7). In this direction, a START bit and logic 0 bit
correspond to a modulated carrier; STOP bit and logic
1 bit correspond to the unmodulated carrier. EOF ends
with an unmodulated carrier instead of STOP bits.
_______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
DATA TO BE TRANSMITTED
847kHz SUBCARRIER
BPSK MODULATION
1
0
1
OR
TRANSMISSION OF A SINGLE BIT
POWER-UP DEFAULT = 8 CYCLES OF 847kHz (9.44μs)
CAN BE REDUCED TO FOUR, TWO, OR ONE SUBCARRIER CYCLES FOR COMMUNICATION IN THE ACTIVE STATE.
INDICATES 180° PHASE CHANGE (POLARITY REVERSAL)
Figure 8. Uplink: BPSK Modulation of the 847.5kHz Subcarrier
DATA*
1
0
1
TRANSMISSION OF A SINGLE BIT
SHOWN AS EIGHT CYCLES OF THE 847kHz SUBCARRIER
*DEPENDING ON THE INITIAL PHASE, THE DATA POLARITY MAY BE INVERSE.
Figure 9. Uplink: Load Modulation of the RF Field by the BPSK Modulated Subcarrier
_______________________________________________________________________________________
5
MAX66000
0° reference, which corresponds to logic 1. The phase
of the subcarrier changes by 180° whenever there is a
binary transition in the character to be transmitted
(Figure 8). The first phase transition represents a
change from logic 1 to logic 0, which coincides with the
beginning of the SOF. The BPSK modulated subcarrier
is used to modulate the load on the device’s antenna
(Figure 9).
The path from slave to master uses an 847.5kHz subcarrier, which is modulated using binary phase-shift
key (BPSK) modulation. Depending on the data rate,
the transmission of a single bit takes eight, four, two, or
one subcarrier cycles. The slave generates the subcarrier only when needed, i.e., starting shortly before an
SOF and ending shortly after an EOF. The standard
defines the phase of the subcarrier before the SOF as
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
PROLOGUE FIELD
INFORMATION FIELD
EPILOGUE FIELD
PCB
CID
NAD
(DATA)
CRC
(LSB)
CRC
(MSB)
1 BYTE
1 BYTE
1 BYTE
0 OR MORE BYTES
1 BYTE
1 BYTE
Figure 10. ISO/IEC 14443-4 Type B Block Format
LSb
MSb
BIT 8
MSb
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 8
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
0
0
0
CH
CID
NAD
1
#
1
0
1
AN
CID
0
1
#
Figure 11. Bit Assignments for I-Block PCB
Figure 12. Bit Assignments for R-Block PCB
ISO/IEC 14443 Block
Transmission Protocol
Before the master can send a data packet to access the
memory, the MAX66000 must be in the ACTIVE state.
The protocol to put the MAX66000 into the ACTIVE state
is explained in the Network Function Commands section. While in the ACTIVE state, the communication
between the master and the MAX66000 follows the
block transmission protocol as specified in Section 7 of
ISO/IEC 14443-4. Such a block (Figure 10) consists of
three parts: the prologue field, the information field, and
the epilogue field. The prologue can contain up to 3
bytes, called the protocol control byte (PCB), card identifier (CID), and the node address (NAD). Epilogue is
another name for the 16-bit CRC that precedes the EOF.
The information field is the general location for data.
Block Types
The standard defines three types of blocks: I-block,
R-block, and S-block. Figures 11, 12, and 13 show the
applicable PCB bit assignments.
The I-block is the main tool to access the memory. For
I-blocks, bit 2 must be 1 and bit 6 to bit 8 must be 0. Bit
5, marked as CH, is used to indicate chaining, a function that is not used or supported by the MAX66000.
Therefore, bit 5 must always be 0. Bit 4, marked as CID,
6
LSb
is used by the master to indicate whether the prologue
field contains a CID byte. The MAX66000 processes
blocks with and without CID as defined in the standard.
The master must include the CID byte if bit 4 is 1. Bit 3,
marked as NAD, is used to indicate whether the prologue field contains an NAD byte, a feature not supported by the MAX66000. Therefore, bit 3 must always be
0. Bit 1, marked as #, is the block number field. The
block number is used to ensure that the response
received relates to the request sent. This function is
important in the error handling, which is illustrated in
Annex B of ISO/IEC 14443-4. The rules that govern the
numbering and handling of blocks are found in
Sections 7.5.3 and 7.5.4 of ISO/IEC 14443-4. The
MAX66000 ignores I-blocks that have bit 5 or bit 3 set
to 1.
For R-blocks, the states of bit 2, bit 3, bit 6, bit 7, and
bit 8 are fixed and must be transmitted as shown in
Figure 12. The function of bit 1 (block number) and bit 4
(CID indicator) is the same as for I-blocks. Bit 5,
marked as AN, is used to acknowledge (if transmitted
as 0) or not to acknowledge (if transmitted as 1) the
reception of the last frame for recovery from certain
error conditions. The MAX66000 fully supports the function of the R-block as defined in the standard. For
details and the applicable rules, refer to Sections 7.5.3
and 7.5.4 and Annex B of ISO/IEC 14443-4.
_______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
LSb
BIT 7
1
1
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
CID
0
1
0
BIT 2
BIT 1
Figure 13. Bit Assignments for S-Block PCB
MSb
LSb
BIT 8
BIT 7
BIT 6
BIT 5
0
0
0
0
(POWER LEVEL)
BIT 4
(FIXED)
BIT 3
CARD IDENTIFIER VALUE
Figure 14. Bit Assignments for CID Byte in I-Blocks
SOF
According to the standard, the slave can use bits 8 and
7 to inform the master whether power-level indication is
supported, and, if yes, whether sufficient power is available for full functionality. Since the MAX66000 does not
support power-level indication, the power-level bits are
always 00b. When the master transmits a CID byte, the
power-level bits must be 00b.
PCB
CID
INFORMATION FIELD
CRC (LSB) CRC (MSB)
EOF
Figure 15. Frame Format for Block Transmission Protocol
For S-blocks, the states of bit 1, bit 2, bit 3, and bit 7
and bit 8 are fixed and must be transmitted as shown in
Figure 13. The function of bit 4 (CID indicator) is the
same as for I-blocks. Bit 5 and bit 6, when 00b, specify
whether the S-block represents a DESELECT command.
If bit 5 and bit 6 are 11b, the S-block represents a
frame-waiting time extension (WTX) request, a feature to
tell the master that the response is going to take longer
than specified by the frame waiting time (FWT) (see the
ATQB Response section). However, the MAX66000
does not use this feature, and, consequently, the only
use of the S-block is to transition the device from the
ACTIVE state to the HALT state using the DESELECT
command (see the Network Function Commands section).
Card Identifier
Figure 14 shows the bit assignment within the card
identifier byte. The purpose of bits 4 to 1 is to select
one of multiple slave devices that the master has elevated to the ACTIVE state. The CID is assigned to a
slave through Param 4 of the ATTRIB command (see
the Network Function Commands section). While in the
ACTIVE state, a compliant slave only processes blocks
that contain a matching CID and blocks without a CID if
the assigned CID is all zeros. If the master includes a
Information Field
Since the MAX66000 does not generate WTX requests,
the information field (Figure 10) is found only with Iblocks. The length of the information field is calculated
by counting the number of bytes of the whole block
minus the length of the prologue and epilogue field.
The ISO/IEC 14443 standard does not define any rules
for the contents of the information field. The MAX66000
assumes that the first byte it receives in the information
field is a command code followed by 0 or more command-specific parameters. When responding to an
I-block, the first byte of the information field indicates
success (code 00h) followed by command-specific
data or failure (code 01h) followed by one error code.
Memory Function Commands
The commands described in this section are transmitted using the block transmission protocol. The data of a
block (from prologue to epilogue) is embedded
between SOF and EOF, as shown in Figure 15. The CID
field (shaded) is optional. If the request contains a CID,
the response also contains a CID.
The command descriptions in this section only show
the information field of the I-blocks used to transmit
requests and responses. Since the MAX66000 neither
supports chaining nor generates WTX requests, when it
receives an I-block, the MAX66000 responds with an
I-block. The block number in the I-block response is the
same as in the I-block request.
Error Indication
In case of an error, the response to a request begins
with a 01h byte followed by one error code.
If there was no error, the information field of the
response begins with 00h followed by command-specific data, as specified in the detailed command
description. If the MAX66000 does not recognize a
command, it does not generate a response.
_______________________________________________________________________________________
7
MAX66000
MSb
BIT 8
CID, then the slave’s response also includes a CID
byte. Blocks with a nonmatching CIDs are ignored.
ISO/IEC 14443 Type B-Compliant
64-Bit UID
MAX66000
Response Information Field for the Get System Information Command (No Error)
INDICATOR
INFO
FLAGS
UID
(DUMMY)
AFI
NUMBER OF
BLOCKS
MEMORY BLOCK
SIZE
IC REFERENCE
00h
0Fh
(8 Bytes)
(1 Byte)
(1 Byte)
02h
07h
(1 Byte)
Response Information Field for the Get UID Command (No Error)
INDICATOR
UID
00h
(8 Bytes)
Detailed Command Descriptions
Get System Information
This command allows the master to retrieve technical
information about the MAX66000. In the response, the
least significant UID byte is transmitted first. The
response is adapted from ISO 15693-3, Section 10. The
IC reference code indicates the die revision in hexadecimal format, such as A1h, A2h, B1h, etc. To receive
the system information, issue a request with the command code 2Bh in the request information field.
Get UID
This command allows the master to retrieve the
device’s unique identification number, UID. In the
response, the least significant UID byte is transmitted
first. To read the UID, issue a request with the command code 30h in the request information field.
8
ISO/IEC 14443-3 Type B Initialization
and Anticollision Protocol
Before an ISO/IEC 14443-compliant RF device gives
access to its memory, a communication path between
the master and the RF device must be established.
Initially, the master has no information whether there are
any RF devices in the field of its antenna. To find out
whether there are one or more RF devices compliant to a
known standard in the field, the master uses a standardspecific initialization and anticollision protocol. The
ISO/IEC 14443 Type B protocol defines six states:
POWER-OFF, IDLE, WAITING FOR SLOT-MARKER,
READY, HALT, and ACTIVE. Figure 16 shows these
states and the conditions under which a slave transitions
between states. For most cases, letters surrounded by
small circles reference the condition under which a transition occurs. The conditions are explained in the legend
to Figure 16. Table 1 explains terms that are used in the
anticollision protocol and in the network function command description.
_______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
MAX66000
RESPONSE LEGEND:
POWER-OFF
OUT OF FIELD
(FROM ANY STATE)
IN FIELD
ANY OTHER
COMMAND
OR CASE
1
ATQB RESPONSE
2
ATTRIB RESPONSE
3
HLTB RESPONSE
4
DESELECT RESPONSE
IDLE
S
A
ANY OTHER
COMMAND
OR CASE
WAITING FOR
SLOT-MARKER*
MS
A
S
B
a
B
1
s
1
READY
1
ANY OTHER
COMMAND OR CASE
b
ATTRIB WITH
MATCHING PUPI
2
HLTB WITH
MATCHING PUPI
EXECUTIVE BLOCK
TRANSMISSION
PROTOCOL FUNCTION
3
4
HALT
DESELECT
(SPECIAL CASE OF A BLOCK TRANSMISSION
PROTOCOL FUNCTION)
ACTIVE
ANY OTHER COMMAND
ANY OTHER COMMAND
*WHEN ENTERING “WAITING FOR SLOT-MARKER,” EACH TAG SELECTS A RANDOM NUMBER R IN THE RANGE OF 1 TO “NUMBER OF SLOTS.”
CONDITIONS LEGEND:
NAME
DESCRIPTION
A (AFI MISMATCH)
REQB/WUPB WITH NONMATCHING AFI
a
WUPB WITH NONMATCHING AFI
B (BYPASS SM)
REQB/WUPB WITH MATCHING AFI AND [(N = 1) OR [R = 1)]
b
WUPB WITH MATCHING AFI AND [(N = 1) OR [R = 1)]
S (SLOT-MARKER)
REQB/WUPB WITH MATCHING AFI AND (N 1) AND (R 1)
s
WUPB WITH MATCHING AFI AND (N 1) AND (R 1)
MS (MATCHING SLOT)
SLOT-MARKER COMMAND WITH SLOT NUMBER = R
RESULT
RETURN TO IDLE
TRANSITION DIRECTLY TO READY
WAIT FOR MATCHING SLOT NUMBER
TRANSITION TO READY WITH MATCHING SLOT-MARKER
Figure 16. ISO/IEC 14443 Type B State Transitions Diagram
_______________________________________________________________________________________
9
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
Table 1. ISO/IEC 14443 Type B Technical Terms
TERM
DESCRIPTION
ACTIVE
One of the slave’s six states. In this state, the memory and control function commands and deselect apply.
ADC
Application Data Coding. 2-Bit field of the 3rd protocol info byte of the ATQB response.
AFI
Application Family Identifier. 1-Byte field used in the REQB/WUPB request to preselect slaves.
ATQB
Answer to Request, Type B. Response to REQB, WUPB, and SLOT-MARKER command.
ATTRIB
Slave Selection Command, Type B. Used to transition a slave from READY to the ACTIVE state.
BPSK
Binary Phase-Shift Keying Modulation
CID
Card Identifier. 4-Bit temporary identification number assigned to a slave through the ATTRIB command, used
in conjunction with the block transmission protocol.
EOF
End of Frame
DESELECT
Slave Deselection Command. Transitions the slave from the ACTIVE state to the HALT state.
fc
Carrier Frequency = 13.56MHz
FO
Frame Option. 2-Bit field of the 3rd protocol info byte of the ATQB response.
fs
Subcarrier Frequency = fc/16 = 847.5kHz
FWI
Frame-Waiting Time Integer. 4-Bit field of the 3rd protocol info byte of the ATQB response.
FWT
Frame-Waiting Time. Calculated from FWI.
HALT
One of the slave’s six states. The master puts a slave in this state to park it.
HLTB
Halt Command, Type B
IDLE
One of the slave’s six states. In this state, the slave has power and is waiting for action.
INF
Information Field for Higher Layer Protocol (per ISO/IEC 14443-4)
MBLI
Maximum Buffer Length Index of Slave (per ISO/IEC 14443-4). 4-Bit field of the first protocol info byte of the
ATQB response.
N
Number of Anticollision Slots (or response probability per slot)
NAD
Node Address (per ISO/IEC 14443-4)
POWER-OFF
One of the slave’s six states. In this state, the slave has no power and consequently cannot do anything.
PUPI
Pseudo Unique Identifier. 4-Byte field of the ATQB response.
R
4-Bit Random Number Chosen by a Slave When Processing the REQB or WUPB Command
READY
One of the slave’s six states; official name is READY-DECLARED SUBSTATE. In this state, the slave has
identified itself and is waiting for transition to ACTIVE (memory functions) or HALT (parking).
REQB
Request Command, Type B. Used to probe the RF field for the presence of slave devices.
RF
Radio Frequency
S
Slot Number. 4-Bit field sent to slave with SLOT-MARKER command.
SLOT-MARKER
Command used in the time-slot approach to identify slaves in the RF field
SOF
Start of Frame
TR0
Guard Time per ISO/IEC 14443-2
TR1
Synchronization Time per ISO/IEC 14443-2
WAITING FOR
SLOT-MARKER
One of the slave’s six states; official name is READY-REQUESTED SUBSTATE. In this state, the slave is
waiting to be called by its random number R to transition to READY.
WUPB
Wake-Up Command, Type B. Similar to REQB, required to wake up slaves in the HALT state.
10
______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
POWER-OFF State
This state applies if the slave is outside the master’s RF
field. A slave transitions to the POWER-OFF state when
leaving the power-delivering RF field. When entering
the RF field, the slave automatically transitions to the
IDLE state.
IDLE State
The purpose of the IDLE state is to have the slave population ready to participate in the anticollision protocol.
When transitioning to the IDLE state, the slave does not
generate any response. To maintain this state, the slave
must continuously receive sufficient power from the
master’s RF field to prevent transitioning into the
POWER-OFF state. While in the IDLE state, the slave listens to the commands that the master sends, but reacts
only on the REQB and WUPB commands, provided that
they include a matching AFI value. If the master sends
a command with a nonmatching AFI byte (conditions A
and a), a transition to IDLE is also possible from the
HALT state, the READY state, and the WAITING FOR
SLOT-MARKER state. From IDLE, a slave can transition
to the higher states READY (condition B) or WAITING
FOR SLOT-MARKER (condition S). For details, see the
REQB/WUPB command description in the Network
Function Commands section.
WAITING FOR SLOT-MARKER State
(READY REQUESTED SUBSTATE)
The WAITING FOR SLOT-MARKER state is used in the
time-slot anticollision approach. A slave can transition
to WAITING FOR SLOT-MARKER from the IDLE, HALT,
or READY state upon receiving a REQB or WUPB command with a matching AFI (conditions S and s), provided that both the number of slots specified in the
REQB/WUPB command and the random number that
the slave has chosen are different from 1. To maintain
this state, the slave must continuously receive sufficient
power from the master’s RF field to prevent transitioning
into the POWER-OFF state. A slave in the WAITING
FOR SLOT-MARKER state listens to the commands that
the master sends, but reacts only on the REQB, WUPB,
and SLOT-MARKER commands. From WAITING FOR
SLOT-MARKER, a slave can transition to the higher
state READY under condition B (bypassing the SLOTMARKER), or MS (matching slot, SLOT-MARKER command with a slot number that matches the random
number R). Condition A (AFI mismatch) returns the
slave to the IDLE state.
READY State (READY DECLARED SUBSTATE)
The READY state applies to a slave that has met the criteria in the anticollision protocol to send an ATQB
response. A slave can transition to READY from IDLE or
HALT (conditions B and b) or from WAITING FOR
SLOT-MARKER (conditions B and MS). When transitioning to the READY state, the slave transmits an ATQB
response. To maintain this state, the slave must continuously receive sufficient power from the master’s RF
field to prevent transitioning into the POWER-OFF state.
A slave in the READY state listens to the commands
that the master sends, but reacts only on the REQB,
WUPB, ATTRIB, and HLTB commands. From READY, a
slave can transition to ACTIVE (ATTRIB command with
matching PUPI), HALT (HLTB command with matching
PUPI), or IDLE (condition A).
HALT State
The HALT state is used to silence slaves that have
been identified and shall no longer participate in the
anticollion protocol. This state is also used to park
slaves after communication in the ACTIVE state was
completed. A slave transitions to the HALT state either
from READY (HLTB command with matching PUPI) or
from ACTIVE (DESELECT command with matching
CID). When transitioning to the HALT state, the slave
transmits a response that confirms the transition. To
maintain this state, the slave must continuously receive
sufficient power from the master’s RF field to prevent
transitioning into the POWER-OFF state. The normal
way out of the HALT state is through the WUPB command. From HALT, a slave can transition to IDLE (condition a), READY (condition b), or WAITING FOR
SLOT-MARKER (condition s).
ACTIVE State
The ACTIVE state enables the slave to process commands sent through the block transmission protocol.
When entering the ACTIVE state, the slave confirms the
transition with a response. The only way for a slave to
transition to the ACTIVE state is from the READY state
(ATTRIB command with a matching PUPI). In the
ATTRIB command, the master assigns a 4-bit CID that
is used to address one of multiple slaves that could all
be in the ACTIVE state. To maintain this state, the slave
must continuously receive sufficient power from the
master’s RF field to prevent transitioning into the
POWER-OFF state. The normal way out of the ACTIVE
state is through the DESELECT command, which transitions the slave to the HALT state.
______________________________________________________________________________________
11
MAX66000
ISO/IEC 14443 Type B States and
Transitions
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
Network Function Commands
To transition slaves devices between states, the
ISO/IEC 14443 Type B standard defines six network
function commands, called REQB, WUPB, SLOTMARKER, HLTB, ATTRIB, and DESELECT. The master
issues the commands in the form of request frames and
the slaves respond by transmitting response frames.
With network function commands, command code,
parameters and response are embedded between SOF
and CRC. This section describes the format of the
response and request frames and the coding of the
data fields inside the frames as detailed as necessary
to operate the MAX66000. Not all of the fields and
cases that the standard defines are relevant for the
MAX66000. For a full description of those fields refer to
the ISO/IEC 14443-3, Section 7.
REQB/WUPB Command
The REQUEST command, Type B (REQB) and the
WAKEUP command, Type B (WUPB) are the general
tools for the master to probe the RF field for the presence of slave devices and to preselect them for action
based on the value of the application family identifier
(AFI). An ISO/IEC 14443 Type B-compliant slave watches for these commands while in the IDLE state,
WAITING FOR SLOT-MARKER state, and READY state.
In the HALT state, the slave only acts upon receiving a
WUPB command. The REQB or WUPB command is
transmitted as a frame, as shown in Figure 17. Besides
the command code, the request includes two parameters, AFI and PARAM. The response to REQB/WUPB is
named ATQB. See the ATQB Response section for
details.
The ISO/IEC 14443 standard defines rules for the
assignment of the AFI codes and the behavior of the
slaves when receiving a REQB/WUPB request. If the
request specifies an AFI of 00h, a slave must process
the command regardless of its actual AFI value. If the
least significant nibble of the AFI in the request is
0000b, the slave must process the command only if the
most significant nibble of the AFI sent by the master
matches the most significant nibble of the slave’s AFI.
For all other AFI values, the slave processes the command only if the AFI in the request and the slave match.
The AFI code is factory programmed to a customerspecific value (default is 00h) and cannot be changed.
The bit assignments of the PARAM byte are shown in
Figure 18. Bits 5 to 8 are reserved and must be transmitted as 0. Bit 4, if 0, indicates that the request is a
REQB command; bit 4, if 1, defines a WUPB command.
Bits 1, 2, and 3 specify the number of slots (N) to be
used in the anticollision protocol. Table 2 shows the
codes. In the case of N = 1, the SLOT-MARKER command does not apply and all slaves with a matching
AFI transition to the READY state. With multiple slaves
in the field, this leads to a data collision, since the
response frames are transmitted simultaneously. If N is
MSb
SOF
COMMAND
AFI
PARAM
CRC
05h
(1 BYTE)
(1 BYTE)
(2 BYTES)
EOF
LSb
BIT 8
BIT 7
BIT 6
BIT 5
0
0
0
0
(FIXED)
Figure 17. REQB/WUPB Request Frame
BIT 4
BIT 3
BIT 2
REQB/
WUPB
N
Figure 18. Bit Assignments for PARAM Byte
Table 2. Number of Slots Codes
12
BIT 3
BIT 2
BIT 1
N
0
0
0
1
0
0
1
2
0
1
0
4
0
1
1
8
1
0
0
16
1
0
1
(RESERVED)
1
1
X
(RESERVED)
______________________________________________________________________________________
BIT 1
ISO/IEC 14443 Type B-Compliant
64-Bit UID
The bits marked as “nnnn” specify the slot number as
defined in the Table 3. Any sequence of the permissible
slot numbers is permitted.
ATQB Response
The response for both the REQB/WUPB and the SLOTMARKER command is called ATQB, which stands for
“answer to request, Type B.” Figure 20 shows the format of the ATQB response. The PUPI field (pseudounique identifier) is used by the master to address a
slave for transitioning to the ACTIVE or HALT state. The
data reported as PUPI is the least significant 4 bytes of
the 64-bit UID. The application data field reports userdefined data that is relevant for distinguishing otherwise
equal slaves in the RF field. The application data field is
factory programmed to reflect the most significant 4
bytes of the 64-bit UID. This allows the master to obtain
the full 64-bit UID in the first response from the slave.
However, this field may be factory-programmed to a
customer-specific value.
SLOT-MARKER Command
Instead of relying on the fact that a participating slave
chooses a new random number for every REQB/WUPB
command, in the “time-slot approach” the master calls
the slaves by their random number R using the SLOTMARKER command. Before this can be done, the master must have issued the REQB/WUPB command with a
number of slots (N) value greater than 1. The master
can send up to (N - 1) SLOT-MARKER commands.
Figure 19 shows the format of the SLOT-MARKER
request frame. The AFI field is not needed since the
slaves have already been preselected through the preceding REQB/WUPB request. The response to the
SLOT-MARKER command is called ATQB. See the
ATQB Response section for details.
SOF
COMMAND
CRC
nnnn0101b
(2 BYTES)
The protocol info field provides the master with administrative information, such as data rate, frame size,
ISO/IEC 14443-4 compliance, frame waiting time, and
whether the slave supports CID and NAD in the
ISO/IEC 14443-4 block transmission protocol. Figure 21
shows where this information is located in the protocol
info field and what the values are.
EOF
SOF
Figure 19. SLOT-MARKER Request Frame
INDICATOR
PUPI
50h
(4 BYTES)
APPLICATION DATA PROTOCOL INFO
(4 BYTES)
(3 BYTES)
CRC
EOF
(2 BYTES)
Figure 20. ATQB Response Frame
Table 3. Slot Numbering
BIT 8
BIT 7
BIT 6
BIT 5
SLOT NUMBER
0
0
0
1
2
0
0
1
0
3
0
0
1
1
4
…
…
…
…
…
1
1
1
0
15
1
1
1
1
16
______________________________________________________________________________________
13
MAX66000
larger than 1, each slave in the field selects its own
4-bit random number, R, in the range of 1 to N. A slave
that happens to choose R = 1 responds to the
REQB/WUPB request. The larger N is the lower the
probability of colliding response frames; however, if N
is 16 and there is only a single slave in the field, it can
take up to 15 SLOT-MARKER commands to get a
response. The method to identify all slaves in the field
relying solely on the random number R and the
REQB/WUPB command is called the “probabilistic
approach.” For mode information about the anticollision
process, see the Anticollision Examples section.
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
3RD BYTE,
UPPER NIBBLE
3RD BYTE,
BIT 4, BIT 3
MAXIMUM FRAME SIZE, PROTOCOL TYPE
FWI
ADC
FO
11h
0110b
00b
01b
1ST BYTE
2ND BYTE
BIT RATE CAPABILITY
77h
3RD BYTE,
BIT 2, BIT 1
Figure 21. Protocol Info Field Details
SOF
COMMAND
PUPI
CRC
50h
(4 BYTES)
(2 BYTES)
SOF
EOF
Figure 22. HLTB Request Frame
CRC
00h
(2 BYTES)
EOF
Figure 23. HLTB Response Frame
The bit-rate capability of the MAX66000 ranges from
105.9kbps to 847.5kbps in both directions (request and
response); request and response bit rate need not be
the same. The maximum frame size (upper nibble of the
2nd byte) of any request/response specifies 24 bytes.
The largest frame that occurs with the MAX66000 is 19
bytes (Get System Information response). The protocol
type (lower nibble of the 2nd byte) specifies that the
MAX66000 supports the ISO/IEC 14443-4 block transmission protocol. The FWI code 0110b specifies a
frame waiting time of 19.3ms. Note that a slave may
respond long before the maximum frame waiting time is
expired. The ADC code 00b specifies that the
MAX66000 uses proprietary coding for the application
data field. The FO code 01b implies that the MAX66000
supports CID, but does not support the NAD field in the
ISO/IEC 14443-4 block transmission protocol.
HLTB Command
The HLTB command is the only network function command to silence a slave by parking it in the HALT state.
If, based on the ATQB response, the master does not
want to further communicate with the slave, the master
issues the HLTB command. Figures 22 and 23 show the
format of the HLTB request frame and the corresponding response frame. The data to be used in the PUPI
field must match the PUPI information that the slave has
transmitted in the ATQB response. While in the HALT
state, the slave only responds to the WUPB request.
SOF
INDICATOR
ATTRIB Command
The ATTRIB command is the only way to select a slave
and make it process commands that are transmitted
according to the ISO/IEC 14443 block transmission protocol. If, based on the ATQB response, the master
wants to communicate with the slave, the master must
put the slave into the ACTIVE state using the slave
selection command ATTRIB. The normal way for the
master to move a slave out of the ACTIVE state is by
sending a DESELECT command, which uses an
S-block to convey a network function command.
Figure 24 shows the format of the ATTRIB request
frame. The data to be used in the PUPI field must
match the PUPI information that the slave has transmitted in the ATQB response. Param 1 tells the slave how
much time the master needs to switch from transmit to
receive (TR0), how much time the master needs to synchronize to the slave’s subcarrier (TR1), and whether
the master is capable of receiving response frames
without SOF and/or EOF.
The MAX66000 ignores the data of Param 1. To ease
requirements for ISO/IEC 14443 Type B readers, the
MAX66000 has TR0 and TR1 fixed at 128/fs (151µs; fs
is the subcarrier frequency of 847.5kHz) and always
begins and ends its responses with SOF and EOF,
respectively.
COMMAND
PUPI
PARAM 1
PARAM 2
PARAM 3
PARAM 4
1Dh
(4 BYTES)
(1 BYTE)
(1 BYTE)
01h
(1 BYTE)
HLINF
CRC
EOF
(≥ 0 BYTES) (2 BYTES)
Figure 24. ATTRIB Request Frame
14
______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
BIT 8
LSb
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
X
X
X
X
RESPONSE DATA REQUEST DATA
RECEIVER FRAME SIZE CAPABILITY
RATE (UPLINK) RATE (DOWNLINK)
Figure 25. Bit Assignments for Param 2 Byte
MSb
LSb
BIT 8
BIT 7
BIT 6
BIT 5
0
0
0
0
BIT 4
(FIXED)
BIT 3
BIT 2
BIT 1
CARD IDENTIFIER VALUE (CID)
Figure 26. Bit Assignments for Param 4 Byte
SOF
INDICATOR
HL RESPONSE
CRC
MBLI, CID
(≥ 0 BYTES)
(2 BYTES)
EOF
Figure 27. ATTRIB Response Frame
FRAME WITHOUT CID
SOF
COMMAND
CRC
C2h
(2 BYTES)
EOF
FRAME WITH CID
SOF
COMMAND
CID
CRC
CAh
(1 BYTE)
(2 BYTES)
EOF
Figure 28. DESELECT Request and Response Frames
Param 2 informs the slave about the data rate that shall
be used for communication in the ACTIVE state and the
maximum frame size that the master can receive.
Figure 25 shows the bit assignments for the Param 2
byte. The MAX66000 supports the data rates of
105.9kbps (code 00b), 211.9kbps (code 01b),
423.75kbps (code 10b), and 847.5kbps (code 11b).
The master can choose different data rates for request
and response. Since it does not support chaining, the
MAX66000 ignores the frame size capability and
assumes that the master can receive frames as large
as specified in the ATQB response.
The lower nibble of Param 3 is used to confirm the protocol type as specified in the lower nibble of the second
byte of the ATQB protocol info. Since ISO/IEC 14443-3
sets the upper nibble of Param 3 to 0000b, the Param 3
value to be used for the MAX66000 in the ATTRIB
request is 01h.
Param 4 assigns the slave the CID number that is used
with the block transmission protocol to address one of
several slaves in the ACTIVE state. Figure 26 shows the
Param 4 bit assignments. Since the MAX66000 supports the CID field, the master can assign any number
in the range from 0 to 14. According to ISO/IEC 144433, code 15 is reserved.
The ATTRIB request frame contains one optional field,
called higher layer information (HLINF). This field can
be used to include data as in the information field of the
ISO/IEC 14443 Type B block transmission protocol (see
Figure 10). If such data is present and the slave supports the HLINF field, then the slave processes the
HLINF data and returns the result in its response to the
ATTRIB request. Typically, the ATTRIB request is transmitted without HLINF field. The only HLINF data that the
MAX66000 accepts and processes is the Get UID command, code 30h.
If the ATTRIB request has a matching PUPI and a valid
CRC, the slave transmits an ATTRIB response frame, as
shown in Figure 27. The upper nibble of the indicator,
also referred to as MBLI, is 0000b, telling that the slave
does not provide any information on its internal input
buffer size; the lower nibble returns the card identifier
value that the master has just assigned to the slave.
The HL response field is optional. There are three
cases to be distinguished:
a) If there was no HLINF field in the ATTRIB request,
then there is no HL response field in the response.
b) If there was a Get UID command code (30h) in the
HLINF field of the ATTRIB request, then the HL
response field is identical to the Get UID response
information field (i.e., 00h followed by the 8-byte UID).
c) If the code in the HLINF field of the ATTRIB request
was different from 30h, then the response frame does
not contain an HL response field.
DESELECT Command
The DESELECT command is used to transition the slave
from the ACTIVE to the HALT state after the master has
completed the communication with the slave. There are
two versions of the deselect request frame, one without
CID and one with CID. Figure 28 shows both versions.
Figure 26 shows the CID format.
______________________________________________________________________________________
15
MAX66000
MSb
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
Logically, the DESELECT command is a special case of
the S-block of the block transmission protocol, as
defined in part 4 of the ISO/IEC 14443 standard. The
MAX66000 responds to a DESELECT command if the
CID in the request and the CID in the device match. If
the DESELECT request does not include a CID, the
MAX66000 only responds to the request if its CID is
0000b.
The response frame to the DESELECT command is
identical to the request frame. The slave returns the
same data that it had received, confirming that the
slave addressed in the request has been transitioned to
the HALT sate.
Anticollision Examples
Probabilistic Anticollision
The master starts the anticollision process by issuing an
REQB or WUPB command. The WUPB command
involves any slave in the field with a matching AFI code.
The REQB command performs the same function, but is
ignored by slaves in the HALT state. Both commands
include the parameter N, which according to Table 2 is
used to set the probability of an ATQB response to 1/N.
If N = 1, all participating slaves respond with the ATQB
response. If N is greater than one, then each slave
selects a random number R in the range of 1 to N. If a
slave happens to choose R = 1, then it responds with
ATQB. If R is greater than 1, then the slave waits for
another REQB or WUPB command, which causes the
participating slaves to choose a new random number R.
The ATQB response contains a field named PUPI,
which is used to direct commands to a specific slave
TESTING FOR SLAVES
MASTER
REQB
(N = 1)
ATTEMPT 1
ATTEMPT 2
during the anticollision process. When the master
receives an ATQB response, it should issue a matching
HLTB command to halt the slave or issue a matching
ATTRIB command to assign a CID and place the slave
in the ACTIVE state. If this is not done, the slaves continue to participate in the anticollision process. A slave
in the ACTIVE state ignores all REQB, WUPB, SLOTMARKER, ATTRIB, and HLTB commands, but responds
to the DESELECT command.
An ATQB response received with a CRC error indicates
a collision because two or more slaves have responded
at the same time. With probabilistic anticollision, the
master must issue another REQB command to cause
the slaves in the field that are not in the HALT or
ACTIVE state to select a new random number R. If one
of the slaves has chosen R = 1, it responds with ATQB.
A REQB without ATQB response does not guarantee that all slaves in the field have been identified.
Figure 29 shows an example of the time-slot anticollision, assuming that there are four slaves in IDLE state in
the field. The process begins with the master sending
an REQB request with N = 1, which forces all slaves to
respond with ATQB, resulting in a collision. Knowing that
slaves are present, the master now sends REQB with
N = 8. This causes all slaves to select a random number
in the range of 1 to 8. Only the slave that has chosen R
= 1 responds, which is slave C in the example. Knowing
that there are more slaves in the field, the master continues issuing REQB commands, which in the example,
eventually identifies all slaves. Due to its statistical
nature, probabilistic anticollision is less likely to find
every slave in the field than the time-slot anticollision.
ATTEMPT 3
ATTEMPT 4 ATTEMPT 5
ATTEMPT 6
REQB
(N = 8)
REQB
(N = 8)
REQB
(N = 8)
REQB
(N = 8)
REQB
(N = 8)
REQB
(N = 8)
SLAVE A
ATQB
(R = 3)
(R = 7)
(R = 1) ATQB
(R = 3)
(R = 6)
(R = 8)
SLAVE B
ATQB
(R = 6)
(R = 4)
(R = 8)
(R = 8)
(R = 5)
(R = 1) ATQB
SLAVE C
ATQB
(R = 1) ATQB (R = 8)
(R = 2)
(R = 4)
(R = 3)
(R = 4)
SLAVE D
ATQB
(R = 2)
(R = 1) ATQB (R = 5)
(R = 8)
(R = 4)
(R = 2)
Figure 29. Probabilistic Anticollision Example
16
______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
MASTER
REQB
(N = 1)
SLOT 1
REQB
(N = 8)
SLAVE A
ATQB
(R = 3)
SLAVE B
ATQB
(R = 6)
SLAVE C
ATQB
(R = 1) ATQB
SLAVE D
ATQB
(R = 2)
SLOT 2
SM2
SLOT 3
SM3
SLOT 4 SLOT 5
SM4
SM5
SLOT 6
SM6
SLOT 7 SLOT 8
SM7
SM8
ATQB
ATQB
ATQB
Figure 30. Time-Slot Anticollision Example
Time-Slot Anticollision
The master starts the anticollision process by issuing
an REQB or WUPB command. The WUPB command
involves any slave in the field with a matching AFI code.
The REQB command performs the same function, but is
ignored by slaves in the HALT state. Both commands
include the parameter N, which according to Table 2
specifies the number of slots to be used in the anticollision protocol.
If N = 1, all participating slaves respond with the ATQB
response. If N is greater than one, then each slave
selects a random number R in the range of 1 to N. If a
slave happens to choose R = 1, then it responds with
ATQB. If R is greater than 1, then the slave waits for a
SLOT-MARKER command with a slot number that is
equal to R and then responds with ATQB. The master
must try all slot numbers from 2 to N to ensure that no
slave is missed.
The ATQB response contains a field named PUPI,
which is used to direct commands to a specific slave
during the anticollision process. When the master
receives an ATQB response, it should issue a matching
HLTB command to halt the slave, or issue a matching
ATTRIB command to assign a CID and place the slave
in the ACTIVE state. A slave in the ACTIVE state ignores
all REQB, WUPB, SLOT-MARKER, ATTRIB, and HLTB
commands, but responds to the DESELECT command.
An ATQB response received with a CRC error indicates
a collision because two or more slaves have responded
at the same time. Typically the master continues issuing
SLOT-MARKER commands to test for slaves with random numbers R different from 1. If additional collisions
were encountered, the master must issue a new REQB
command, causing each slave in the field that is not in
the HALT or ACTIVE state to select a new random number R. The anticollision process then continues in this
manner until all slaves in the field have been identified
and put either into the HALT or ACTIVE state.
Figure 30 shows an example of the time-slot anticollision, assuming that there are four slaves in IDLE state
in the field. The process begins with the master sending an REQB request with N = 1, which forces all slaves
to respond with ATQB, resulting in a collision. Knowing
that slaves are present, the master now sends REQB
with N = 8. This causes all slaves to select a random
number in the range of 1 to 8. This does not prevent
two slaves from choosing the same value for R, but the
higher N is, the less likely this is to occur. In the example, slave C has chosen R = 1 and responds right after
REQB. The master now sends a SLOT-MARKER command with slot number 2 (SM2), which causes slave D
to respond. The master continues testing all slots, and,
if a slave with matching R is present, receives an
ATQB. In case the master detects a collision in a slot,
the slaves identified in the remaining slots need to be
put in the HALT or ACTIVE state first, before another
anticollision process is started. Note that there is no
need for the master to test the slots in numerical order,
as in the example.
______________________________________________________________________________________
17
MAX66000
TESTING FOR SLAVES
MAX66000
ISO/IEC 14443 Type B-Compliant
64-Bit UID
CRC Generation
The ISO/IEC 14443 standard uses a 16-bit CRC, generated according to the CRC-16-CCITT polynomial function: X16 + X12 + X5 + 1 (Figure 31). This CRC is used
for error detection in request and response data packets and is always communicated in the inverted form.
POLYNOMIAL = X16 + X12 + X5 + 1
MSb
1ST
STAGE
X0
After all data bytes are shifted into the CRC generator,
the state of the 16 flip-flops is parallel-copied to a shift
register and shifted out for transmission with the LSb
first. For more details on this CRC refer to ISO/IEC
14443-3, Annex B, CRC_B encoding.
3RD
STAGE
2ND
STAGE
X2
X1
4TH
STAGE
X3
5TH
STAGE
6TH
STAGE
X4
X5
7TH
STAGE
X6
8TH
STAGE
X7
LSb
9TH
STAGE
X8
10TH
STAGE
X9
11TH
STAGE
X10
12TH
STAGE
X11
13TH
STAGE
X12
14TH
STAGE
X13
15TH
STAGE
X14
16TH
STAGE
X15
X16
INPUT DATA
Figure 31. CRC-16-CCITT Generator
18
______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
SYMBOL
DESCRIPTION
GSY
Command “Get System Information”
GUID
Command “Get UID”
SOF
Start Of Frame
PCB
Protocol Control Byte (see section ISO/IEC 14443 Block Transmission Protocol for details)
[CID]
The tag’s assigned card identifier (see section Network Function Commands for details). The brackets [ ]
indicate that the transmission of the CID depends on the Protocol Control Byte (PCB).
CRC-16
Transmission of an inverted CRC-16 (2 bytes) generated according to CRC16-CCITT.
EOF
End Of Frame
IND
Response indicator byte
IFLG
Info Flags byte
UID
The tag’s unique 8-byte identification number
DB
Dummy byte
AFI
Application Family Identifier byte
NBLK
Number of Blocks byte (slave memory size indicator)
MBS
Memory Block Size byte (slave memory block size)
ICR
IC-Reference byte (slave chip revision)
Command-Specific ISO/IEC 14443 Communication Protocol—Color Codes
Master-to-Slave
Slave-to-Master
ISO/IEC 14443 Communication Examples
Precondition: The slave device is already in the ACTIVE state. See section Network Function Commands on how to
enter and exit the ACTIVE state.
Get System Information
SOF PCB [CID] GSY CRC-16 EOF
Success
(Carrier)
SOF IND = 00h IFLG UID DB AFI NBLK MBS ICR CRC-16 EOF
Get UID
SOF PCB [CID] GUID CRC-16 EOF
Success
(Carrier)
SOF IND = 00h UID CRC-16 EOF
______________________________________________________________________________________
19
MAX66000
Command-Specific ISO/IEC 14443 Communication Protocol—Legend
ISO/IEC 14443 Type B-Compliant
64-Bit UID
MAX66000
Mechanical Drawings
TOP VIEW
54mm
7.7mm
28mm
MAX66000K-000AA+
1.6mm
SIDE VIEW
KEY FOB
TOP VIEW
85.60mm
14.29mm
MAX66000E-000AA+
3.49mm
53.98mm
0.76mm
SIDE VIEW
ISO CARD
20
______________________________________________________________________________________
ISO/IEC 14443 Type B-Compliant
64-Bit UID
REVISION
NUMBER
REVISION
DATE
0
1/11
DESCRIPTION
Initial release
PAGES
CHANGED
—
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 21
© 2011 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX66000
Revision History