ASSALOY Identification Technologies RDHC 0502N0 0X Users Manual
www.acg.de
ACG HF Mifare Easy Module
Document No.: 1503-USM-01-0-01
Firmware: Version 1.0
User Manual
ACG Identification Technologies GmbH
Am Klingenweg 6A
65396 Walluf
Germany
Phone +49 (0) 6123 791 0
Fax +49 (0) 6123 791 199
rfid@acg.de
Document Nr.: QSI-040902-OM-1-a-UserManual Dual ISO Module, V2.0
HF Mifare Easy Module V1.0
Edition One - April 2005
ACG Identification Technologies GmbH (ACG) reserves the right to make changes to
its products or services or to discontinue any product or service at any time without
notice. ACG provides customer assistance in various technical areas, but does not
have full access to data concerning the use and applications of customer's products.
Therefore, ACG assumes no liability and is not responsible for customer applications
or product or software design or performance relating to systems or applications
incorporating ACG products. In addition, ACG assumes no liability and is not
responsible for infringement of patents and/or any other intellectual or industrial
property rights of third parties, which may result from assistance provided by ACG.
ACG products are not designed, intended, authorized or warranted to be suitable for
life support applications or any other life critical applications that could involve potential risk of death, personal injury or severe property or environmental damage.
With the edition of this document, all previous editions become void. Indications
made in this manual may be changed without previous notice.
Composition of the information in this manual has been done to the best of our
knowledge. ACG does not guarantee the correctness and completeness of the
details given in this manual and may not be held liable for damages ensuing from
incorrect or incomplete information. Since, despite all our efforts, errors may not be
completely avoided, we are always grateful for your useful tips.
The installation instructions given in this manual are based on advantageous
boundary conditions. ACG does not give any guarantee promise for perfect function
in cross environments.
The ACG logo is a registered trademark of ACG Identification Technologies GmbH.
Copyright © 2005 ACG Identification Technologies GmbH (ACG)
This document may be downloaded onto a computer, stored and duplicated as nec-
essary to support the use of the related ACG products. Any other type of duplication,
circulation or storage on data carriers in any manner not authorized by ACG
represents a violation of the applicable copyright laws and shall be prosecuted.
ACG Identification Technologies GmbH 1
HF Mifare Easy Module V1.0
Safety Instructions / Warning - Read before start-up!
• The device may only be used for the intended purpose designed by for the
manufacturer. The operation manual should be conveniently kept available at
all times for each user.
• Unauthorized changes and the use of spare parts and additional devices that
have not been sold or recommended by the manufacturer may cause fire,
electric shocks or injuries. Such unauthorized measures shall exclude any
liability by the manufacturer.
• The liability-prescriptions of the manufacturer in the issue valid at the time of
purchase are valid for the device. The manufacturer shall not be held legally
responsible for inaccuracies, errors, or omissions in the manual or
automatically set parameters for a device or for an incorrect application of a
device.
• Repairs may be executed by the manufacturer only.
• Only qualified personnel should carry out installation, operation, and
maintenance procedures.
• Use of the device and its installation must be in accordance with national legal
requirements and local electrical codes.
• When working on devices the valid safety regulations must be observed.
ACG Identification Technologies GmbH 2
HF Mifare Easy Module V1.0
Preface
Read This First
About This Guide
This manual describes the HF Mifare Easy Read/Write Module. Its goal is to describe
the reader, how it works, how to integrate it and how to use it.
If You Need Assistance
Our application center is located in Europe to provide direct support. For more
information, please contact your nearest ACG Sales Center. The contact addresses
can be found on our home page:
http://www.acg.de
ACG Identification Technologies GmbH 3
HF Mifare Easy Module V1.0
Table of contents
1 Scope...............................................................................................8
2 Extended Documentation...............................................................8
3 Definitions and abbreviations........................................................8
3.1 Definitions .................................................................................................... 8
3.1.1 Anticollision loop ................................................................................... 8
3.1.2 Hex notation.......................................................................................... 8
3.1.3 ASCII notation....................................................................................... 8
3.2 Abbreviations................................................................................................ 9
4 Supported tags..............................................................................10
5 The Mifare transponder family.....................................................11
5.1 State Diagram ............................................................................................ 11
5.2 Mifare Standard.......................................................................................... 12
5.2.1 Definitions ........................................................................................... 12
5.2.2 Sector 0 / Block 0................................................................................ 13
5.2.3 Block 3, 7, 11, 15, …........................................................................... 13
5.3 Mifare Ultralight.......................................................................................... 13
5.4 Mifare 4k .................................................................................................... 14
5.5 Mifare ProX ................................................................................................ 14
5.6 Mifare DESFire........................................................................................... 15
5.6.1 Memory organization........................................................................... 15
5.6.2 State diagram of DESFire ................................................................... 16
5.6.2.1 Activate PICC............................................................................... 16
5.6.2.2 Select application with ID............................................................. 16
5.6.2.3 Login to application...................................................................... 16
5.6.2.4 Select file with ID ......................................................................... 17
5.6.2.5 Change file................................................................................... 17
5.6.2.6 Commit/ Abort transaction............................................................ 17
6 Hardware .......................................................................................18
6.1 Pin out of OEM Module (Top View)............................................................ 18
6.1.1 Pin out................................................................................................. 19
6.1.2 Electrical characteristics of PINs......................................................... 20
6.1.3 External Connections.......................................................................... 21
6.1.3.1 Power Supply............................................................................... 21
6.1.3.2 Antenna........................................................................................ 22
6.1.3.3 Serial Interface............................................................................. 22
6.1.3.4 Function Control LEDs................................................................. 23
7 Software.........................................................................................24
7.1 ASCII Protocol............................................................................................ 24
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HF Mifare Easy Module V1.0
7.2 Binary Protocol........................................................................................... 24
7.2.1 STX..................................................................................................... 24
7.2.2 Station ID ............................................................................................ 24
7.2.3 Length................................................................................................. 24
7.2.4 Data .................................................................................................... 25
7.2.5 Block Check Character (BCC)............................................................. 25
7.2.6 ETX..................................................................................................... 25
7.2.7 Remarks.............................................................................................. 25
7.2.8 Examples ............................................................................................ 26
7.3 Register Set................................................................................................ 26
7.3.1 EEPROM memory organization.......................................................... 26
7.3.2 Unique device ID (00h – 03h).............................................................. 26
7.3.3 StationID (04h).................................................................................... 27
7.3.4 Protocol configuration (05h)................................................................ 27
7.3.4.1 Autostart (default 1) ..................................................................... 27
7.3.4.2 Protocol (default 0)....................................................................... 27
7.3.4.3 Extended ID (default 0)................................................................ 28
7.3.4.4 Binary Timeout (default 0)............................................................ 28
7.3.4.5 Multitag (default 0)....................................................................... 28
7.3.5 BAUD, Baud rate control register (0Ch).............................................. 29
7.3.6 Reset Off Time (07h)........................................................................... 29
7.3.7 Reset Recovery Time (08h) ................................................................ 30
7.3.8 User data (10h - 13h).......................................................................... 30
7.4 Instruction Set ............................................................................................ 31
7.4.1 Overview............................................................................................. 31
7.4.2 Error Codes......................................................................................... 32
7.4.3 Common commands........................................................................... 33
7.4.3.1 Increment value block (credit)...................................................... 33
7.4.3.1.1 No value block 'I'....................................................................... 33
7.4.3.1.2 Increment failure 'F'................................................................... 33
7.4.3.1.3 No tag error 'N'.......................................................................... 33
7.4.3.1.4 Unable to read after write 'X'..................................................... 34
7.4.3.2 Decrement value block (debit) ..................................................... 34
7.4.3.2.1 No value block 'I'....................................................................... 34
7.4.3.2.2 Decrement failure 'F'................................................................. 34
7.4.3.2.3 No tag error 'N'.......................................................................... 35
7.4.3.2.4 Unable to read after write 'X'..................................................... 35
7.4.3.3 Copy value block (backup)........................................................... 35
7.4.3.3.1 Target block.............................................................................. 36
7.4.3.3.2 No value block 'I'....................................................................... 36
7.4.3.3.3 Copy failure 'F'.......................................................................... 36
7.4.3.3.4 No tag error 'N'.......................................................................... 36
ACG Identification Technologies GmbH 5
HF Mifare Easy Module V1.0
7.4.3.3.5 Unable to read after write 'X'..................................................... 36
7.4.3.4 Continuous Read......................................................................... 37
7.4.3.4.1 Multitag continuous read mode................................................. 37
7.4.3.4.2 Auto start.................................................................................. 37
7.4.3.4.3 Binary mode.............................................................................. 37
7.4.3.4.4 Simple access control applications........................................... 38
7.4.3.4.5 Extended ID.............................................................................. 38
7.4.3.5 Get Station ID .............................................................................. 38
7.4.3.5.1 Time slotted answer.................................................................. 39
7.4.3.6 Login (authenticate tag) ............................................................... 40
7.4.3.6.1 No tag error 'N'.......................................................................... 41
7.4.3.6.2 <CR>........................................................................................ 41
7.4.3.6.3 Login with keydata from EEPROM ........................................... 42
7.4.3.6.4 Usage of key A, key B............................................................... 42
7.4.3.7 Multi Tag Selection / List.............................................................. 42
7.4.3.7.1 Multi tag list............................................................................... 43
7.4.3.7.2 Reading distance...................................................................... 43
7.4.3.7.3 Multi tag select.......................................................................... 43
7.4.3.7.4 Multi tag reset........................................................................... 43
7.4.3.7.5 Maximum number of tags......................................................... 43
7.4.3.8 Antenna power on/off................................................................... 44
7.4.3.8.1 Power off................................................................................... 44
7.4.3.8.2 Power on................................................................................... 44
7.4.3.8.3 Reset Timing............................................................................. 44
7.4.3.9 Read/Write user port.................................................................... 45
7.4.3.9.1 Read port.................................................................................. 45
7.4.3.9.2 Write port.................................................................................. 46
7.4.3.10 Read block................................................................................... 46
7.4.3.10.1 Read failure 'F'........................................................................ 47
7.4.3.10.2 No tag in field 'N'..................................................................... 47
7.4.3.10.3 Operation mode failure 'O'...................................................... 47
7.4.3.11 Read reader EEPROM................................................................. 47
7.4.3.12 Read value block ......................................................................... 48
7.4.3.12.1 No value block 'I'..................................................................... 48
7.4.3.12.2 No tag error 'N'........................................................................ 48
7.4.3.12.3 General failure 'F'.................................................................... 48
7.4.3.13 Select........................................................................................... 49
7.4.3.13.1 Select a single tag................................................................... 49
7.4.3.13.2 Extended ID............................................................................ 49
7.4.3.13.3 Multiple tags............................................................................ 49
7.4.3.14 Get Version.................................................................................. 50
7.4.3.15 Write block................................................................................... 51
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HF Mifare Easy Module V1.0
7.4.3.15.1 Write failure 'F'........................................................................ 51
7.4.3.15.2 No tag error 'N'........................................................................ 51
7.4.3.15.3 Operation mode failure 'O'...................................................... 52
7.4.3.16 Write EEPROM............................................................................ 52
7.4.3.17 Write master key.......................................................................... 53
7.4.3.17.1 Writing master keys................................................................ 53
7.4.3.17.2 Using master keys for authentication...................................... 53
7.4.3.18 Write value block.......................................................................... 54
7.4.3.18.1 Invalid value 'I' ........................................................................ 54
7.4.3.18.2 Write failure 'F'........................................................................ 54
7.4.3.18.3 No tag error 'N'........................................................................ 54
7.4.3.18.4 Writing values......................................................................... 55
7.4.3.19 Reset............................................................................................ 55
7.4.3.19.1 Reset Timing........................................................................... 55
8 Frequently Asked Questions........................................................56
8.1 Getting Started........................................................................................... 56
8.2 How should the Mifare Easy Reader be personalized?.............................. 56
8.3 What type of Mifare
8.4 How safe is Mifare
8.5 Mifare
8.5.1 Examples ............................................................................................ 60
8.5.1.1 Ticketing Applications .................................................................. 60
8.5.1.2 Data Handling Applications.......................................................... 60
8.5.1.3 No Security, open configuration................................................... 60
8.6 Using a Mifare card.................................................................................... 60
®
Standard Sector Trailer and Access Conditions............................ 59
®
card should I use?.................................................... 57
®
Standard for cashless payment?................................ 58
9 References ....................................................................................61
10
Appendix A: Antenna.................................................................62
11
Appendix B: Compact P&P Module..........................................63
12
Appendix C: Short Range P&P Module....................................65
13
Appendix D: Timings.................................................................67
14
Appendix E: Release Notes.......................................................68
14.1 Version History........................................................................................... 68
14.1.1 Mifare 1.0............................................................................................ 68
14.2 Revision history.......................................................................................... 68
15
Appendix F: CE Declaration......................................................69
16
Appendix G: FCC Declaration...................................................70
ACG Identification Technologies GmbH 7
HF Mifare Easy Module V1.0
1 Scope
The MIFARE® Application Oriented Protocol is a reader Interface to communicate
with MIFARE® transponders. The major applications to be supported are:
• Access control, Identification: Reading the serial numbers of all cards in
the field.
• Data Storage: Performing encrypted read and write operations.
• Ticketing: Performing read, write, increment and decrement operations
in an encrypted environment.
• Multi applications: Performing read, write, increment and decrement
operations on various sectors of the MIFARE® Standard tags using
different encryption keys.
2 Extended Documentation
Please note that all confidential materials are not part of this documentation.
You can obtain an extended documentation containing that material after signing a
NDA.
3 Definitions and abbreviations
3.1 Definitions
3.1.1 Anticollision loop
Algorithm processed to identify and handle a dialogue between reader and one or
more tags in its antenna field.
3.1.2 Hex notation
A hexadecimal value is noted with a following h, i.e. A1h has the value A1
hexadecimal.
3.1.3 ASCII notation
ASCII characters are listed within apostrophes, i.e. ‘x’ means a single x.
ACG Identification Technologies GmbH 8
HF Mifare Easy Module V1.0
3.2 Abbreviations
Abbreviation Description
ASCII American Standard Code for Information Interchange
block For Mifare® Standard one block contains 16 bytes
EOF End of frame
hex / xxh value in Hexadecimal notation
LSB Least Significant Bit or Byte
MSB Most Significant Bit or Byte
PCON Protocol Configuration byte of the reader
REQA Request ISO Type A
RFU Reserved for Future Use
sector For Mifare® Standard one sector contains 4 blocks
SID Station ID
SN Serial Number of a tag
SOF Start of frame
value block 32 bit data block format. Used in ticketing application
<CR> Carriage return (0Dh)
<LF> Line feed (0Ah)
Figure 3-1: Abbreviations
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ACG Identification Technologies GmbH 10
command
4 Supported tags
HF Mifare Easy Module V1.0
Figure 4-1: Supported labels
Mifare Standard
Mifare 4k
Mifare Ultralight
Mifare ProX
DESFire
Smart MX
SLE44R35S
SLE55R04/08/16
SLE66R35
Manufacturer
Philips
Philips
Philips
Philips
Philips
Philips
Infineon
Infineon
Infineon
Serial
number
√
√
√
√
√
√
√
√
√
Read
bock
√
√
√
√
-
-
√
-
√
Write
block
√
√
√
√
-
-
√
-
√
Transfer
√
√
√
√
√
√
√
√
√
Comments
encryption not included
encryption not included
HF Mifare Easy Module V1.0
Reset
REQA
Select
Authenticat
HALT
Login
5 The Mifare transponder family
The Mifare transponder family consists of various 13.56 MHz transponders IC, all
according to ISO 14443.
5.1 State Diagram
All Mifare cards use following state diagram.
POWER OFF
reader instruction set
IDLE
Select
READY
ISO 14443 commands
HALT
ACTIVE
Anticollision loop
read/write/…
AUTHENTICATED
Tag interfacing
commands
Figure 5-1: State diagram
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HF Mifare Easy Module V1.0
5.2 Mifare Standard
The Mifare Standard card consists of 16 sectors. A sector includes four blocks 16
bytes each.
MIFARE
Sector 0 (Block: 0...3) Block 8: Data or value (16 bytes)
Sector 1 (Block: 4...7) Block 9: Data or value (16 bytes)
Sector 2 (Block 8...11) Block 10: Data or value (16 bytes)
...
Sector 15 (Block 60...63)
®
Standard Sector 2
Block 11: Access Conditions (4
bytes), Key A,
Key B (16 bytes)
Figure 5-2: MIFARE® Standard: sector diagram
5.2.1 Definitions
Sector Memory segment of the MIFARE® Standard Card. Each
segment consists of 4 blocks and has individual keys and
access conditions. Typically in a multiapplication
environment each block is assigned to an application.
Key 6 byte structure assigned to each sector of the card. The
reader may store up to 32 keys in its EEPROM or one key in
its RAM.
Transport Key Key as stored after delivery from the manufacturer.(f.e.
A0A1A2A3A4A5, B0B1B2B3B4B5 or FFFFFFFFFFFF)
Block 16 byte memory segment of the MIFARE® Standard card.
Value 4 byte (unsigned long) variable stored in a special format in
a block or page. Values are 2s complement numbers that
can be negative also. Values are used for cashless payment.
Values consume a complete block each using redundancy
for integrity checking.
Card ID 4 byte unique serial number (single size type). Together with
manufacturer code and check byte 16 bytes. Read-only. It Is
stored in block 0 (sector 0) of each tag.
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HF Mifare Easy Module V1.0
5.2.2 Sector 0 / Block 0
Block 0 is read only.
Serial Number (4 byte)
Figure 5-3: MIFARE Standard: sector 0 / block 0
Check byte (1 byte) Manufacturer data (11 byte)
5.2.3 Block 3, 7, 11, 15, …
Transport keys are set on delivery:
Key A (6 byte) Access Conditions (4 bytes) Key B (6 byte)
Figure 5-4: MIFARE® Standard: block 3, 7, 11, 15, …
Key A
A0 A1 A2 A3 A4 A5 (Infineon) or FF FF FF FF FF FF (new Philips cards)
Key B
B0 B1 B2 B3 B4 B5 (Infineon) or FF FF FF FF FF FF (new Philips cards)
Access Conditions
FF 07 80 xx (key A used to read or write, the key A itself is not readable; key B is
data only). For further information refer to Frequently asked questions or Mifare card
manual.
Remarks
Enabled keys are always read as 00 00 00 00 00 00
Using key B as data area will cause a security gap, due to the fact that it is necessary
to rewrite key A and access conditions each write process. It is not recommended to
use it as data storage.
5.3 Mifare Ultralight
Mifare Ultralight cards have no encryption included. They only support plain text data
transmission.
Mifare Ultralight are only supporting 4 byte per sector, but the command set uses 16
byte per sector. Only the 4 least significant bytes are valid when using Mifare
Ultralight.
Ensure that the other bytes matching with tag content when using the write
command, otherwise the read back will fail.
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HF Mifare Easy Module V1.0
5.4 Mifare 4k
Mifare 4k cards have an increased memory. Beginning from sector 32 (20h) a sector
has 16 blocks. Due to compatibility reasons the sector indices has changed
according following figure. The login sector has to be used to access the according
sector on the card.
Sector Block Login sector
00h 00h – 03h 00h
01h 04h – 07h 01h
… … …
1Fh 7Ch – 7Fh 1Fh
20h 80h – 8Fh 20h
21h 90h – 9Fh 24h
22h A0h – AFh 28h
23h B0h – BFh 2Ch
24h C0h – CFh 30h
25h D0h – DFh 34h
26h E0h – EFh 38h
27h F0h – FFh 3Ch
Figure 5-5: Mifare 4k sector index table
5.5 Mifare ProX
Mifare ProX tags have an operating system onboard. Data organization depends on
the operating system installed on the card. These cards can include additional
functionalities such as DES or a proprietary encipher algorithm.
Prior to any access of the operating system the card must be selected. Customized
commands are issued using the transfer command.
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HF Mifare Easy Module V1.0
DESFire card (Applica
tion 0)
Application 1
Application 2
5.6 Mifare DESFire
This tag supports additional security algorithms (DES, Triple-DES, MAC) for security
sensitive applications.
DESFire tags are addressed using a specific command set (see DESFire command
set).
5.6.1 Memory organization
The memory of a DESFire card can be personalized to own requirements. The card
can be seen as data storage like a hard disk in a PC. The memory is divided in up to
28 different applications (directories) and with 16 files each. An application has up to
14 keys. Depending on keys and access conditions a file can be accessed in four
different ways. Plain data is never secured. Data is secured using a MAC, single
DES or triple DES enciphers.
Following figure describes the memory organization of a DESFire card.
File
ID 1
File
ID 3
File
ID 2
…
File
ID 1
File
ID 3
File
ID 2
…
…
ACG Identification Technologies GmbH 15
Figure 5-6: DESFire memory organization
HF Mifare Easy Module V1.0
5.6.2 State diagram of DESFire
Activate DESFire card
Select application
Login to application
Select file
Change file
Commit / Abort
transaction
Figure 5-7: DESFire State diagram
5.6.2.1 Activate PICC
Prior to any access to a DESFire card the card must be selected. A DESFire card
has 7 bytes UID. After activation the card is powered up and ready to accept a
DESFire command. Application 0 is selected automatically.
5.6.2.2 Select application with ID
To jump into another application it has to be selected. An application can be seen as
a directory, which contains up to 16 files. The size of the application depends on the
stored files.
5.6.2.3 Login to application
Each application can be set to specific access rights. A login to an application allows
changing the application organization. Login to a file opens a secured file for access.
A file can be accessed in four different ways: plain with no security, secured with
MAC, single DES or triple DES.
ACG Identification Technologies GmbH 16
HF Mifare Easy Module V1.0
5.6.2.4 Select file with ID
Prior to any access to a file a file must be selected
5.6.2.5 Change file
A selected file can be changed according its access rights. If a file is secured a login
is needed before.
5.6.2.6 Commit/ Abort transaction
Value files, backup files, linear record files and cyclic record files only adapt its value
after the commit transaction command. Several files can be changed within an
application at the same time. The abort transactions command annulates all changes
within an application. Power loss will cancel all modifications too.
For more details about the application settings and access rights refer to [2].
ACG Identification Technologies GmbH 17
HF Mifare Easy Module V1.0
6 Hardware
6.1 Pin out of OEM Module (Top View)
All dimensions are listed in mm.
30,50
29,21
1,27
1
J1
20
1,27
10
11
2,54
J2
25,40
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HF Mifare Easy Module V1.0
6.1.1 Pin out
PIN PIN Nr Description
ARX 1 Antenna RX
ATX1 2 Antenna TX1
VDD 3 +5 V DC (4.5VDC to 5.5VDC)
GND 4 Ground
ATX2 5 Antenna TX2
TGND 6 Antenna Ground
RFU 7 Reserved for future use
RFU 8 Reserved for future use
RFU 9 Reserved for future use
RFU 10 Reserved for future use
RX 11 RX from PC
TX 12 TX to PC
DIR 13 Direction of RS 485
USER 14 User Port
RES 15 Hardware reset if logic low
EN 16 Enable reader, open or logic high
LEDr 17 LED red
LEDg 18 LED green (reading LED)
GND 19 Ground
VDD 20 +5 V DC (4.5VDC to 5.5VDC)
Figure 6-1: Pin out
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HF Mifare Easy Module V1.0
6.1.2 Electrical characteristics of PINs
PIN PIN Nr Voltage Current
Description
(max)
RX
TX
11
12
USART1 - To RS232, RS485 or
RS422 device driver
USER 14 TTL2 25 mA User sets logic state
RES 15 TTL - Hardware reset if logic
low
EN 16 TTL - Low will disable the
reader device
LEDr 17 TTL 25 mA Logic Low, used for LED
LEDg 18 TTL 25 mA
With 330 Ω (internal
serial) resistor
ARX
ATX1
ATX2
TGND
1
2
5
6
(depends
on antenna
tuning)
200 mA
Antenna input
PP
Antenna output
Antenna output (GND)
RF-Output: approx
150mW at 50 Ohms
RFU 7,8,9,10 - - Not connected
GND 4,19 GND - Supply Ground
VDD 3,20 +5 V DC
150 mA Supply Voltage
(+4.5V DC
to +5.5
VDC)
DIR 13 TTL 25 mA RS485 direction
Figure 6-2: Electrical characteristics of pins
1
Universal Synchronous Asynchronous Receiver Transmitter
2
TTL buffer output / input
ACG Identification Technologies GmbH 20
HF Mifare Easy Module V1.0
6.1.3 External Connections
6.1.3.1 Power Supply
If the supply voltage and any noise modulated on the supply voltage remains within
the specified limits, no further filtering is required. In some cases it is recommended
to use additional filtering for the power supply line. Insuficcient power line filtering
could cause unexpected or irregular performance drops.
Option 1
+5V DC
OEM Board
20
19
uC
Option 2
+5V DC
OEM Board
3
4
The board can be connected as shown above. Both alternatives are possible and can
be used as they fit best into the layout of the carrier board. The two VCC PINs and
the two GND PINs are connected internally.
ACG Identification Technologies GmbH 21
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