ISO/IEC 18092:2004

INTERNATIONAL ISO/IEC
STANDARD 18092
First edition
2004-04-01
Information technology —
Telecommunications and information
exchange between systems — Near Field
Communication — Interface and Protocol
(NFCIP-1)
Technologies de l'information — Télécommunications et échange
d'information entre systèmes — Communication de champ proche —
Interface et protocole (NFCIP-1)

Reference number
©
ISO/IEC 2004
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©  ISO/IEC 2004
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ii © ISO/IEC 2004 – All rights reserved

Contents Page
Foreword. v
Introduction . vi
1 Scope. 1
2 Conformance. 1
3 Normative references. 1
4 Terms and definitions. 1
5 Conventions and notations. 4
5.1 Representation of numbers . 4
5.2 Names. 4
6 Acronyms. 4
7 General. 5
8 RF field. 6
8.1 Passive Communication Mode . 6
8.2 Active Communication Mode. 6
8.3 External RF field threshold value . 6
9 RF Signal Interface. 6
9.1 Bit duration. 6
9.2 Active communication mode. 7
9.2.1 106 kbps. 7
9.2.2 212 kbps and 424 kbps. 9
9.3 Passive communication mode. 10
9.3.1 106 kbps Initiator to Target . 10
9.3.2 106 kbps Target to Initiator . 11
9.3.3 212 kbps and 424 kbps Initiator to Target . 11
9.3.4 212 kbps and 424 kbps Target to Initiator . 12
10 General Protocol flow. 12
11 Initialization. 13
11.1 RF Collision Avoidance. 13
11.1.1 Initial RF Collision Avoidance . 13
11.1.2 Response RF Collision Avoidance. 15
11.2 Passive communication mode. 16
11.2.1 Initialisation and Single Device Detection at 106 kbps .16
11.2.2 Initialisation and SDD at 212 kbps and 424 kbps . 29
11.3 Active communication mode. 32
11.3.1 Initialisation at 106, 212, and 424 kbps . 32
11.3.2 Active communication mode RF Collision Avoidance. 32
12 Transport Protocol. 33
12.1 Transport Data. 33
12.2 Passive communication mode Activation flow. 34
12.3 Active communication mode Activation flow .34
12.4 Commands. 37
12.5 Activation of the protocol. 37
12.5.1 Attribute Request and Response Commands.37
12.5.2 Wakeup Request and Response Commands. 43
12.5.3 Parameter Selection Request and Response Commands. 45
12.6 Data Exchange Protocol. 48
© ISO/IEC 2004 – All rights reserved iii

12.6.1 Data Exchange Protocol Request and Response.48
12.6.2 Response timeout extension .51
12.6.3 Attention – Target present.52
12.6.4 Protocol operation.52
12.6.5 Multi Activation.52
12.6.6 More information (Chaining) .53
12.7 Deactivation of the protocol.53
12.7.1 Deselect Request and Response command.54
12.7.2 Release Request and Response commands.55
Annex A (normative) CRC calculation.57
A.1 CRC for Active and Passive communication mode at 106 kbps .57
A.2 Example of CRC calculation at 106 kbps.57
A.3 CRC for Active and Passive communication mode at 212 kbps and 424 kbps .58
A.4 Example of CRC calculation at 212 kbps and 424 kbps.58

iv © ISO/IEC 2004 – All rights reserved

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 18092 was prepared by ECMA (as ECMA-340) and was adopted, under a special “fast-track
procedure”, by Joint Technical Committee ISO/IEC JTC 1, Information technology, in parallel with its approval
by national bodies of ISO and IEC.

© ISO/IEC 2004 – All rights reserved v

Introduction
This International Standard specifies the interface and protocol for simple wireless communication between
close coupled devices. These Near Field Communication (NFC) devices communicate with transfer rates of
106, 212, and 424 kbps.
This NFC Interface and Protocol (NFCIP-1) standard allows, but does not specify, applications in network
products and consumer equipment.

vi © ISO/IEC 2004 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 18092:2004(E)

Information technology — Telecommunications and information
exchange between systems — Near Field Communication —
Interface and Protocol (NFCIP-1)
1 Scope
This International Standard defines communication modes for Near Field Communication Interface and
Protocol (NFCIP-1) using inductive coupled devices operating at the centre frequency of 13,56 MHz for
interconnection of computer peripherals. It also defines both the Active and the Passive communication
modes of Near Field Communication Interface and Protocol (NFCIP-1) to realize a communication network
using Near Field Communication devices for networked products and also for consumer equipment. This
International Standard specifies, in particular, modulation schemes, codings, transfer speeds, and frame
format of the RF interface, as well as initialization schemes and conditions required for data collision control
during initialization. Furthermore, this International Standard defines a transport protocol including protocol
activation and data exchange methods.
Information interchange between systems also requires, at a minimum, agreement between the interchange
parties upon the interchange codes and the data structure.
2 Conformance
A system implementing the Active and the Passive communication mode shall be in conformance with this
International Standard if it meets all the mandatory requirements specified herein.
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ITU-T V.41:1988, Code-independent error-control system
4 Terms and definitions
For the purposes of this International Standard, the following definitions apply.
4.1
active communication mode
move in which both the Initiator and the Target use their own RF field to enable the communication
4.2
ASK modulation
Amplitude Shift Keying, in which the amplitude of the carrier frequency is modulated according to the logic of
the data to be transmitted
NOTE The degree of modulation is expressed by (a − b)/(a + b) × 100 [%], where a and b respectively represent the
maximum and minimum amplitudes of the modulated signal waveform.
© ISO/IEC 2004 – All rights reserved 1

4.3
Binary Coded Decimal (BCD)
a system for representing each of the decimal numbers 0 to 9 by a four-bit binary code
NOTE The bits, from left to right, are worth 8, 4, 2 and 1 respectively in decimal, so for example the number 6 in BCD
is 0110.
4.4
collision
transmission by two or more Targets or Initiators during the same time period, such that the Initiator or the
Target is unable to distinguish from which Target the data originated
4.5
frame
sequence of data bits and optional error detection bits, with frame delimiters at start and end
4.6
H
Threshold
the minimum value of an external RF field that a NFCIP-1 device shall detect in order not to disturb ongoing
communication by ensuring that its own RF field is switched off
4.7
initiator
generator of the RF field and starter of the NFCIP-1 communication
4.8
load modulation
process of amplitude modulating a radio frequency field by varying the properties of a resonant circuit placed
within the radio frequency field
4.9
lsb first
least significant bit first, indicating a serial data transmission system that sends lsb before all other bits
4.10
LSB first
Least Significant Byte first, indicating a serial data transmission system that sends LSB before all other bytes
4.11
Manchester coding
method of bit coding whereby a logic level during a bit duration is represented by a sequence of two defined
physical states of a communication medium
NOTE The order of the physical states within the sequence defines the logical state. The coding system which
divides into half at the changing point in the middle point of bit self-sustaining time, and makes the direction of the changes
correspond to two logic value.
4.12
modulation index
defined as (a – b)/(a + b) where a and b are the peak and the minimum signal amplitude respectively with the
value of the index possibly expressed as a percentage
NOTE When the maximum amplitude of the modulated signal waveform is set to a and the minimum value is set to b,
the degree of abnormal conditions is usually expressed as a percent.
4.13
msb first
most significant bit indicating a serial data transmission system that sends the msb before all other bits
2 © ISO/IEC 2004 – All rights reserved

4.14
MSB first
Most Significant Byte indicating a serial data transmission system that sends the MSB before all other bytes
4.15
NFCIP-1 device
general term for either an Initiator or a Target communicating in the Active or the Passive communication
mode
4.16
NFC Identifier (NFCIDn)
a randomly generated number used by the RF Collision Avoidance and Single Device Detection sequence for
both the Active and the Passive communication modes
4.17
passive communication mode
when the Initiator is generating the RF field and the Target responds to an Initiator command in a load
modulation scheme
4.18
RF Collision Avoidance (RFCA)
method to detect the presence of a RF field based on the carrier frequency and method to detect and resolve
collisions on protocol level
4.19
SEL_PAR
total number of valid bits of NFCID1 CLn including SEL_CMD and SEL_PAR transmitted by the Initiator
4.20
sensing
an NFCIP-1 device in the Active communication mode expecting a Response to a Request it has sent on the
RF field to detect the start of communication to receive the Request
4.21
Single Device Detection (SDD)
an algorithm used by the initiator to detect one out of several Targets in its RF field
4.22
subcarrier
signal of frequency (fs) used to modulate a carrier of frequency (fc)
4.23
Target
responds to Initiator command either using load modulation scheme (RF field generated by Initiator) or using
modulation of self generated RF field
4.24
Time Period
defines the number of slots used for RF Collision Avoidance
4.25
Time Slot
method of preparing a time window when a Target answers, and assigning and identifying two or more logic
channels
4.26
transaction
includes the initialization and the transparent data exchange between an Initiator and a Target either in the
Active or the Passive communication mode
© ISO/IEC 2004 – All rights reserved 3

5 Conventions and notations
5.1 Representation of numbers
The following conventions and notations apply in this document unless otherwise stated.
 Letters and digits in parentheses represent numbers in hexadecimal notation.
 The setting of bits is denoted by ZERO or ONE.
 Numbers in binary notation and bit patterns are represented by strings of digits 0 and 1 shown with the
most significant bit to the left. Within such strings, X may be used to indicate that the setting of a bit is not
specified within the string.
5.2 Names
The names of basic elements, e.g. specific fields, are written with a capital initial letter.
6 Acronyms
ALL_REQ Wake up ALL Request
ASK Amplitude Shift Keying
ATR Attribute Request and Attribute Response
ATR_REQ Attribute Request
ATR_RES Attribute Response
BCC NFCID1 CLn check byte, calculated as exclusive-or over the 4 previous bytes
BCD Binary Code Decimal
bd Bit duration
BRi Receiving bit duration supported by Initiator
BRt Receiving bit duration supported by Target
BSi Sending bit duration supported by Initiator
BSt Sending bit duration supported by Target
CLn Cascade Level n, 3 ≥ n ≥ 1
CMD Command
CRC Cyclic Redundancy Check
CT Cascade Tag
D Divisor
DEP Data Exchange Protocol Request and Data Exchange Protocol Response
DEP_REQ Data Exchange Protocol Request
DEP_RES Data Exchange Protocol Response
DIDi Initiator Device ID
DIDt Target Device ID
DRi Data rate Received by initiator
DRt Data rate Received by initiator
DSi Data rate Send by initiator
DSL Deselect Request and Deselect Response
DSL_REQ Deselect Request
DSL_RES Deselect Response
DSt Data rate Send by Target
fc Frequency of operating field (carrier frequency)
fd Baseband frequency of Manchester coding
FRT Frame Response Time
fs Frequency of subcarrier (fc/16)
Gi Optional information field for Initiator
Gt Optional information field for Target
ID Identification number
lsb least significant bit
4 © ISO/IEC 2004 – All rights reserved

LSB Least Significant Byte
MI Multiple Information link for Data Exchange Protocol
msb most significant bit
MSB Most Significant Byte
NAD Node Address
NFCID1 Random Identifier for single device detection in the Passive communication
mode at 106 kbps
nfcid1n Byte number n of NFCID1
NFCID2 Random ID for SDD in the Passive communication mode at 212 kbps and 424 kbps
nfcid2n Byte number n of the Random Identifier NFCID2
NFCID3 Random ID for transport protocol activation
nfcid3n Byte number n of the Random Identifier NFCID3
P Odd parity bit
PA Preamble
pdu protocol data unit
PFB Control information for transaction
PNI Packet Number Information
PPi Protocol Parameters used by Initiator
PPt Protocol Parameters used by Target
PSL Parameter Selection Request and Parameter Selection Response
PSL_REQ Parameter Selection Request
PSL_RES Parameter Selection Response
RF Radio Frequency
RFCA RF Collision Avoidance
RFU Reserved for Future Use
RLS Release Request and Release Response
RLS_REQ Release Request
RLS_RES Release Response
RWT Response Waiting Time
SB Start byte for data exchange protocol at 106 kbps
SDD Single Device Detection
SDD_REQ Single Device Detection Request command
SEL_CMD Select Command byte
SEL_PAR Select Parameter byte
SEL_REQ Select Request command
SENS_REQ Sense Request command
SENS_RES Sense Response command
SLP_REQ Sleep Request command
SYNC Synchronous pattern
TO Timeout value
WT Waiting Time
WUP Wakeup Request and Wakeup Response
WUP_REQ Wakeup Request
WUP_RES Wakeup Response
7 General
This International Standard defines both the Active and the Passive communication modes as follows:
In the Active communication mode, both the Initiator and the Target shall use their own RF field to enable
communication. The Initiator starts the NFCIP-1 communication. The Target responds to an Initiator command
in the Active communication mode using self-generated modulation of self-generated the RF field.
In the Passive communication mode, the Initiator generates the RF field and starts the communication. The
Target responds to an Initiator command in the Passive communication mode using a load modulation
scheme.
© ISO/IEC 2004 – All rights reserved 5

The communication over the RF interface in the Active and the Passive communication mode shall include
modulation schemes, transfer speed and bit coding. In addition it shall include the start of communication, the
end of communication, the bit and byte representation, the framing and error detection, the single device
detection, the protocol and parameter selection and the data exchange and de-selection of Near Field
Communication Interface and Protocol (NFCIP-1) devices.
All NFCIP-1 devices shall have communication capability on 106 kbps and may switch to another transfer
speed or stay at 106 kbps. All NFCIP-1 devices shall have communication capability on 212 kbps and may
switch to another transfer speed or stay at 212 kbps. All NFCIP-1 devices shall have communication
capabilities on 424 kbps and may switch to another transfer speed or stay at 424 kbps.
The mode (Active or Passive) shall not be changed during one transaction until the deactivation of the Target
or removal of the Target, even though the transfer speed of Initiator to Target and the transfer speed of the
Target to the Initiator may not be the same. The change of transfer speed during one transaction may be
performed by a parameter change procedure.
The transaction is started by device initialisation and terminated by device de-selection (or equivalent).
8 RF field
The carrier frequency of the RF field shall be 13,56 MHz.
The minimum unmodulated RF field shall be H and has a value of 1,5 A/m rms.
min
The maximum unmodulated RF field shall be H and has a value of 7,5 A/m rms.
max
This field shall be modulated during communication.
8.1 Passive Communication Mode
An Initiator shall produce a RF field to energise the target.
A Target shall operate continuously between H and H .
min max
8.2 Active Communication Mode
An Initiator and a Target shall alternately generate a RF field of at least H and not exceeding H at
min max
manufacturer specified positions (operating volume).
8.3 External RF field threshold value
NFCIP-1 devices shall detect external RF fields at 13,56MHz with a value higher than H while
Threshold
performing external RF field detection.
The threshold value is H = 0,1875 A/m.
Threshold
9 RF Signal Interface
9.1 Bit duration
The bit duration bd is calculated by the following formula:
1 bd = 128/(D × fc)
6 © ISO/IEC 2004 – All rights reserved

The values of the divisor D depend on the bit rate and are given by Table 1. The fc is the carrier frequency as
defined in clause 8.
Table 1 — Definition of Divisor D
Communication Mode kbps Divisor D
active or passive 106 1
active or passive 212 2
active or passive 424 4
Active 847 8
Active 1 695 16
Active 3 390 32
Active 6 780 64
NOTE The Initiator for starting the communication chooses the initial bit rate.
9.2 Active communication mode
The specification of both from the Initiator to the Target and from the Target to the Initiator shall be identical.
9.2.1 106 kbps
9.2.1.1 Bit rate
The bit rate for the transmission during initialisation and single device detection shall be fc/128 (106 kbps).
9.2.1.2 Modulation
Communication from the Initiator to a Target and a Target to the Initiator for a bit rate of fc/128 shall use the
modulation principle of ASK 100 % of the RF operating field to create a “Pulse” as shown in Figure 1.
The envelope of the field shall decrease monotonically to less than 5 % of its initial value H and remain
INITIAL
less than 5 % for more than t2. (See Table 2.) This envelope shall comply with Figure 1.
If the envelope of the field does not decrease monotonically, the time between a local maximum and the time
of passing the same value before the local maximum shall not exceed 0,5 µs. This shall only apply if the local
maximum is greater than 5 % of H .
INITIAL
Overshoots shall remain within 90 % and 110 % of H .
INITIAL
The Target shall detect the “End of Pulse” after the field exceeds 5 % of H and before it exceeds 60 %
INITIAL
of H . The “End of Pulse” is defined by t4 in Table 2. This definition applies to all modulation envelope
INITIAL
timings.
© ISO/IEC 2004 – All rights reserved 7

(H/HINITIAL)
Envelope of carrier amplitude
110%
100%
90%
60%
5%
t
5%
60%
90%
100% t4
110%
t2
t3
t1
Figure 1 — Pulse shape
Table 2 — Pulse shape value
Pulses length t1 [µs] t2 [µs] t3 [µs] t4 [µs]
(t1 u 2,5)
(Condition)
(t1 > 2,5)
Maximum 3,0 t1 1,5 0,4
Minimum 2,0 0,7 0,5 0,0 0,0
9.2.1.3 Bit representation and coding
The following coding shall be used:
 Start of communication: at the beginning of the bit duration a “Pulse” shall occur.
 ONE: after a time of half the bit duration a “Pulse” shall occur.
 ZERO: For the full bit duration no modulation shall occur with the following two exceptions:
 If there are two or more contiguous ZEROs, from the second ZERO on a Pulse shall occur at the
beginning of the bit duration.
 If the first bit after a “start of communication” is ZERO, a ‘Pulse’ shall occur at the beginning of the bit
duration.
 End of Communication: ZERO followed by one bit duration without modulation.
 No information: shall be coded with at least two full bit duration without modulation.
8 © ISO/IEC 2004 – All rights reserved

t
9.2.1.4 Byte encoding
The byte encoding shall be least significant bit (lsb) first.
9.2.2 212 kbps and 424 kbps
9.2.2.1 Bit rate
The bit rates for the transmission during initialisation and single device detection shall respectively be fc/64
(212 kbps) or fc/32 (424 kbps).
9.2.2.2 Modulation
The Initiator and the Target shall use the modulation of ASK with the modulation index of 8 % to 30 % of the
operating field. The modulation waveform shall comply with Figure 2. The rising and falling edges of the
modulation shall be monotonic. The modulation for the transmission during initialisation and single device
detection shall be the same. a and b define the peak and the minimum signal amplitude. See 4.11.
Table 3 — Modulated waveform
212 kbps 424 kbps
tf 2,0 µs max 1,0 µs max
tr 2,0 µs max 1,0 µs max
y 0,1 (a – b) 0,1 (a – b)
hf, hr 0,1 (a – b) max 0,1 (a – b) max

Figure 2 — Modulated Waveform
© ISO/IEC 2004 – All rights reserved 9

9.2.2.3 Bit representation and coding
Manchester bit encoding shall be employed. The waveform is shown in Figure 3 and Figure 4. Bit coding
format is Manchester with logic levels defined as:
Logic “ZERO”: The first half of a bit is carrier low field amplitude, and the second half of the bit shall be carrier
high field amplitude (no modulation applied).
Logic “ONE”: The first half of a bit is carrier high field amplitude (no modulation applied), and the second half
of the bit shall be carrier low field amplitude.
Reverse polarity in amplitude shall be permitted. Polarity shall be detected from the SYNC.
1 bit 1 bit
ZERO
ONE
Figure 3 — Manchester bit encoding (obverse amplitude)

1 bit 1 bit
ONE ZERO
Figure 4 — Manchester bit encoding (reverse amplitude)
9.2.2.4 Byte encoding
The byte encoding shall be most significant bit (msb) first.
9.3 Passive communication mode
9.3.1 106 kbps Initiator to Target
9.3.1.1 Bit rate
The bit rate for transmission during initialisation and single device detection from the Initiator to the Target in
the Passive communication mode shall be the same as the bit rate for communication from Initiator to the
Target in the Active communication mode. See 9.2.1.1.
9.3.1.2 Modulation
The modulation for transmission during initialisation and single device detection from the Initiator to the Target
in the Passive communication mode shall be the same as the modulation for communication from Initiator to
the Target in the Active communication mode. See 9.2.1.2.
10 © ISO/IEC 2004 – All rights reserved

9.3.1.3 Bit representation and coding
The bit representation and coding for the transmission during initialisation and single device detection from the
Initiator to the Target in the Passive communication mode shall be the same as the bit representation and
coding for communication from Initiator to the Target in the Active communication mode. See 9.2.1.3.
9.3.1.4 Byte encoding
The byte encoding shall be least significant bit (lsb) first. See 9.2.1.4.
9.3.2 106 kbps Target to Initiator
9.3.2.1 Bit rate
The bit rate for the transmission during initialisation and single device detection shall be fc/128.
9.3.2.2 Modulation
The Target shall respond to the Initiator via an inductive coupling area where the carrier frequency is loaded to
generate a subcarrier with frequency fs. The subcarrier shall be generated by switching a load in the Target.
1,2
The load modulation amplitude shall be at least 30/H (mV peak) where H is the (rms) value of magnetic
field strength in A/m.
9.3.2.3 Subcarrier Frequency
The frequency fs of the subcarrier shall be fc/16.
9.3.2.4 Subcarrier modulation
Every bit period shall start with a defined phase relation to the subcarrier. The bit period shall start with the
loaded state of the subcarrier.
The subcarrier shall be modulated with the sequences defined in clause 9.3.2.5.
9.3.2.5 Bit representation and coding
The Bit representation and coding is defined in clause 9.2.2.3 and shown in Figure 3 Manchester Coding with
obverse amplitude. Reverse polarity in amplitude shall be not allowed.
9.3.2.6 Byte encoding
The byte encoding shall be least significant bit (lsb) first.
9.3.3 212 kbps and 424 kbps Initiator to Target
9.3.3.1 Bit rate
The bit rate for transmission during initialisation and single device detection from the Initiator to the Target in
the Passive communication mode shall be the same as the bit rate for communication from Initiator to the
Target in the Active communication mode. See 9.2.2.1.
© ISO/IEC 2004 – All rights reserved 11

9.3.3.2 Modulation
The modulation for transmission during initialisation and single device detection from the Initiator to the Target
in the Passive communication mode shall be the same as the modulation for communication from Initiator to
the Target in the Active communication mode. See 9.2.2.2.
9.3.3.3 Bit representation and coding
The bit representation and coding for the transmission during initialisation and single device detection from the
Initiator to the Target in the Passive communication mode shall be the same as the bit representation and
coding for communication from Initiator to the Target in the Active communication mode. See 9.2.2.3.
9.3.3.4 Byte encoding
The byte encoding is defined in clause 9.2.2.4.
9.3.4 212 kbps and 424 kbps Target to Initiator
9.3.4.1 Bit rate
The bit rate for transmission during initialisation and single device detection from the Initiator to the Target in
the Passive communication mode shall be the same as the bit rate for communication from Initiator to the
Target in the Active communication mode. See 9.2.2.1.
9.3.4.2 Modulation
The Target shall be capable of communication to the Initiator via an inductive coupling area where the carrier
frequency is loaded to generate a Manchester coding with bit duration bd. (See 9.2.) The Manchester coding
shall be generated by switching a load in the Target.
1,2
The load modulation amplitude shall be at least 30/H (mV peak) where H is the (rms) value of magnetic
field strength in A/m.
9.3.4.3 Bit representation and coding
The bit representation and coding for the transmission during initialisation and single device detection from the
Target to the Initiator in the Passive communication mode shall be the same as the bit representation and
coding for communication in the Active communication mode. See 9.2.2.3.
9.3.4.4 Byte encoding
The byte encoding is defined in clause 9.2.2.4.
10 General Protocol flow
The General Protocol flow between NFCIP-1 devices shall be conducted through the following consecutive
operations:
 Any NFCIP-1 device shall per default be in Target mode.
 When in Target mode, it shall not generate an RF field, and shall wait silently for a command from the
Initiator.
 The NFCIP-1 device may switch to Initiator mode only if required by the application.
 The application shall determine either Active or Passive communication mode and transfer speed.
12 © ISO/IEC 2004 – All rights reserved

 Initiator shall test for external RF field present and shall not activate its RF field if an external RF field is
detected. See clause 8.3.
 If an external RF field is not detected, the Initiator shall activate its RF field.
 The Target shall be activated by the RF field of the Initiator.
 Transmission of a command by the Initiator either in the Active communication mode or in the Passive
communication mode at a selected transfer speed.
 Transmission of a response by the Target either in the Active communication mode or in the Passive
communication mode. The communication mode and the transfer speed shall be the same as the Initiator
communication mode and the transfer speed.
Figure 5 shows the general initialisation and single device detection flow for the Active and the Passive
communication mode at different transfer speeds.
The General Protocol flow describes the flow to initialise and select the Targets either in the Passive
communication mode or in the Active communication mode using one of the chosen transfer speeds. RF
Collision Avoidance is described in clause 11.1. Passive communication mode is described in clause 11.2.
The initialisation and SDD for 106 kbps is described in clause 11.2.1, initialisation and SDD for 212 kbps and
424 kbps is described in clause 11.2.2. The Active communication mode is described in clause 11.3.
The Activation of the Protocol is described in clause 12.5. The Parameter Selection is described in clause
12.5.3. The Data Exchange Protocol is described in clause 12.6. The Deactivation is described in clause 12.7.
11 Initialization
This section describes the initialization and collision detection protocol for Targets in the Active and the
Passive communication mode. The Initiator shall detect a collision that occurs, when at least two Targets
simultaneously transmit bit patterns with one or more bit positions where they transmit complementary values.
Figure 5 shows the general initialization and Single Device Detection flow for the Active and the Passive
communication mode at different transfer speeds.
11.1 RF Collision Avoidance
In order not to disturb any other NFC communication and any current infrastructure running on the carrier
frequency, an Initiator for NFC communication shall not generate its own RF field as long as another RF field
is detected.
11.1.1 Initial RF Collision Avoidance
To start communication with the Target device either in the Active or the Passive communication mode an
Initiator shall sense continuously for the presence of an external RF field. See clause 8.3.
If the Initiator detects no RF field within the timeframe T + n × T the RF field shall switch on. The
IDT RFW
integer value of n is randomly generated. Figure 6 illustrates the initial RF Collision Avoidance during
initialisation.
© ISO/IEC 2004 – All rights reserved 13

Start
Initial RF Collision
Avoidance
RF field detected ?
Yes
No
Application switches to
Application switches to
initiator mode for Passive
initiator mode for Active
communication mode and
communication mode
chooses the tranfer speed
and chooses transfer
and performs the initialisation
speed
and the SDD
Activation in Passive Activation in Active
communication mode communication mode
Protocol
by NFCID3 (ATR) by NFCID3 (ATR)
Activation
Parameter selection Parameter
(PSL)
Selection
Data
Data exchange protocol Exchange
(DEP) Protocol
De-Activation
De-
(DSL,RLS)
Activation
End transaction
Figure 5 — General initialization and single device detection flow

Send Request
RF On
TRFW
Start
TIRFG
TIDT
n x TRFW
.
Figure 6 — Initial RF Collision Avoidance
14 © ISO/IEC 2004 – All rights reserved

Transport Protocl Initialisation

T : Initial delay time. T > 4 096 / fc
IDT IDT
T : RF waiting time. 512 / fc
RFW
n: randomly generated number of Time Periods for T .
RFW
0 u n u 3
T : Initial guard-time between switching on RF field and start to send command or data frame.
IRFG
T > 5 ms
IRFG
The RF field, which is generated by the Initiator, shall be switched off in the Active communication mode. The
RF field, which is generated by the Initiator, shall not be switched off in the Passive communication mode.
11.1.2 Response RF Collision Avoidance
In addition to the initial RF Collision Avoidance as described in clause 11.1.1. A response RF collision
avoidance during activation shall be required in the Active communication mode to avoid collision of data by
simultaneous responding of more than one target. Figure 7 illustrates the response RF Collision Avoidance
sequence during initialisation.
Send Response
RF On
TRFW
Start
TADT TARFG
n x TRFW
.
Figure 7 — Response RF Collision Avoidance sequence during activation

T : Active delay time, sense time between RF off Initiator/Target and Target/Initiator.
ADT
(768/fc u T u 2 559/fc)
ADT
T : RF waiting time. (512/fc)
RFW
n: Randomly generated number of Time Periods for T . (0 u n u 3)
RFW
T : Active guard time between switching on RF field and start to send command. (T > 1024/fc)
ARFG ARFG
© ISO/IEC 2004 – All rights reserved 15

11.2 Passive communication mode
11.2.1 Initialisation and Single Device Detection at 106 kbps
11.2.1.1 Frame format and timing
This section defines the frame format and timing used during initialisation and Single Device Detection in
passive communication mode at 106 kbps. For bit representation and coding. See 9.3.1.3.
Before the communication starts the initiator has to perform the initial RF Collision Avoidance as described in
clause 11.1.1.
Data Frames shall be transferred in pairs, the Initiator initiates the communication followed by the response of
the Target.
The Initiator Frame format includes the start of communication, the information and the end of communication.
See Table 4.
Table 4 — Initiator Frame format
Start of communication Information End of communication (End)
(Start)
 Frame Response time between Initiator and Target.
 The Target frame format includes the start of communication, the information and the end of
communication. See Table 5.
Table 5 — Target Frame format
Start of communication Information End of communication (End)
(Start)
 Frame Response time Target to Initiator.
The Frame Response time (FRT) from Target to Initiator overlaps the Initiator end of communication.
11.2.1.2 Frame Response Time Initiator to Target
The Frame Response Time is the time between the end of the last pulse transmitted by the Initiator and the
first modulation edge within the start bit transmitted by the Target Table 6 defines values for n and FRT
depending on the command type and the logic state of the last transmitted data bit in this command.
Table 6 — Frame Response Time (Initiator to Target)
Command type n (integer value) FRT
last pulsed bit = ONE last pulsed bit = ZERO
SENS_REQ
ALL_REQ
SDD_REQ
SEL_REQ
(n × 128 + 84) / fc (n × 128 + 20) / fc
All other commands W 9
16 © ISO/IEC 2004 – All rights reserved

The value n = 9 means that all Targets in the field shall respond in a synchronous way which is needed for
Single Device Detection. For all other commands the Target shall ensure that the first modulation edge within
the start bit is aligned to the bi
...