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What is a Smart Card?

What is a Smart Card?
Smart cards are typically credit card sized, plastic credentials containing a microprocessor chip that serves the dual functions of communication and extensive data storage. Although it is packaged in the form of a card, a smart card operates much like a personal computer in that it can store data, manipulate data, and perform functions like mathematical equations. Smart cards normally contain application fields/sectors secured by special, application-specific security keys (much like keys that unlock various rooms in a building). These sectors can contain information for various applications – such as access control, cashless vending, mass transit, and payment systems – securely separated from one other by security keys. Smart cards can come in two forms: contact and contactless. Contact smart cards operate much like magnetic stripe cards (credit cards, etc.), requiring insertion into or direct contact with a reader. Contactless cards are read when presented near or in “proximity” to a reader.

Contact Smart Cards
Most cards originally introduced in the market were contact smart cards. This technology contains hundreds of times the storage capacity of its predecessor, the magnetic stripe card. Although most new applications of smart cards appear to be heading toward contactless technology, contact smart cards are still the standard for logical (computer) access and some other applications, such as payment systems in Europe.

Contactless Smart Cards
Contactless cards should not be confused with their predecessor – the proximity card. Although both technologies transmit data via radio frequency (and the visible operation of each appears the same to a user), a contactless card provides much greater security and contains 100 times the data storage of a traditional proximity card. Most new applications of smart cards, such as payments systems, are currently running pilots in anticipation of transitioning to contactless technology.

ISO Standards Governing Smart Cards
The International Standards Organization (ISO) is a network of 148 countries’ institutes of standards that provides consensus for decisions governing standards for various products worldwide. Members include one representative per nation, including both government and private sector individuals. Decisions made by the ISO affect both business and government standards.
ISO 7816 is the ISO standard governing contact smart cards. The standard covers physical characteristics, dimensions and contact locations, transmission protocols, commands for interchange, application identifier systems and data elements.
ISO 14443 is a four-part contactless standard consisting of physical card characteristics, radio frequency power and signal interference, initialization and anti-collision and transmission protocols. The operating frequency defined in this standard is 13.56 MHz, providing a read range up to 4 inches (10 cm). There are two types of ISO
14443: Type A and Type B. Although originally meant to serve different functions, both Type A and Type B are now microprocessor standards similar in function. However, ISO 14443A is the more commonly used technology, while Type B is used primarily in banking applications. Due to faster data speeds, 14443 technology is recommended for applications in which extensive amounts of data, such as large biometric templates, need to be transmitted. Anticipating an increase in data-intensive applications requiring high data rates, the U.S. government recently selected IS 14443 as its official standard.
ISO 15693 is a 13.56 MHz technology referred to as vicinity because it provides greater operational read ranges, making it the preferred choice for many high-traffic locations like access control.
Proximity can refer to ISO14443 or to the older 125 kHz technology traditionally used in access control. 125 kHz proximity is not “smart” technology and is not governed by ISO standards. 125 kHz proximity is typically proprietary, requiring that cards and readers be purchased from the same vendor.
Unique Identifier (UID): All ISO-compliant smart cards are provided with a UID number (akin to a VIN number on a vehicle). For
interoperability purposes, a card’s UID is open and available to be read by all compliant readers. Since this unique number is not secured by keys, reading the UID of a smart card is comparable to reading a proximity card, mag stripe card or other technology that utilizes open, unsecured numbers.

Advantages of Contactless Smart Cards
There are a number of advantages to consider when comparing contactless technology to contact smart cards and 125
kHz proximity cards:
1. Convenience: Given the choice, users will virtually always choose contactless over contact technology. Contactless smart card users do not have to worry about where to insert the card, how to insert the card, or how fast to slide the card.
2. Less Maintenance/Warranty: Contactless smart cards require very little wear and tear maintenance because they contain no moving parts and require no points of contact. As a result, most contactless smart cards come with lifetime warranties covering defects and workmanship.
3. Higher Security: Contactless smart cards are uniquely capable of providing optimal transmission security with optional encryption and mutual authentication features. Mutual authentication is a three-way communication process between a card and reader using hashed, encrypted messages to authenticate each other without broadcasting a shared secret key.
4. Large Memory: Contactless cards have a data storage capacity hundreds of times greater than that of a proximity card. Contactless smart cards can also process information, calculate mathematical formulas and perform other computing functions.
5. Enhanced Privacy: Even large biometric templates can be stored and verified using a single contactless smart card, allowing private information to stay in the possession of the card holder instead of being stored in a data base.
6. Versatile Form Factors: Unlike its contact counterparts, contactless smart communication can utilize a variety of credential technologies. Keychain fobs, watches and even stickers can be used as contactless credentials.
7. Multiple Applications: Carrying a contactless smart card is like carrying many cards in one. A single contactless smart card can manage multiple applications such as access control, payment systems, cashless vending, paring, mass transit, etc. Additional features and applications can be added to a contactless smart card as user needs evolve.
8. Future Protection: Contactless smart card technology will no doubt soon replace mag stripe and proximity technologies. Choosing contactless products now will avoid the use of obsolete and outdated systems while providing the best avenue for system expandability.

Card Technology Overview
MIFARE is a 13.56 MHz contactless technology family of microprocessors developed by Philips. MIFARE® is the most common contactless chipset on the market and is used in many applications around the globe. It is an ISO 14443 product that ensures compatibility with future products. Cards can be purchased that contain memory up to 32k bits, a capacity robust enough to process the largest biometric templates while still incorporating other applications.
DESFire is a high-end chipset in the MIFARE® family that is the first chip compliant with the Government Smart Card Interoperability Specification (GSC-IS). The GSC-IS standard was created to ensure the interoperability of contactless and contact smart cards throughout the federal government.
MIFARE DESFire™ EV1 is based on open global standards for both air interface and cryptographic methods. It is compliant to all 4 levels of ISO / IEC 14443A and uses optional ISO / IEC 7816-4 commands. MIFARE DESFire™ EV1 card can hold up to 28 different applications and 32 files per application. The size of each file is defined at the moment of its creation, making MIFARE DESFire™ EV1 a truly flexible and convenient product.
DES Encryption is a strong cryptographic algorithm protecting classified information. It is a public algorithm determined by the National Institute of Standards and Technology (NIST) to be open, inexpensive, widely available and – most of all – very secure.
Triple DES is slower than regular DES but its longer key length and triple encryption process is billions of times more secure. Its advantage over other security algorithms is that it is based on the DES algorithm, making it easy to modify existing software to incorporate triple DES. Triple DES is also public with proven reliability.
AES (Advanced Encryption Standard) is a symmetric-key encryption standard adopted by the U.S. government.AES is slower than DES, but faster than Triple DES. AES-128 (128 bit key) and was the first publicly accessible and open cipher approved by NSA for top secret info.
my-d® is a 13.56 MHz contactless technology family of microprocessors developed by Infineon Technologies, one of the world’s leading semiconductor companies. Its advanced security algorithms also make it a worldwide leader in ISO 15693 contactless technology.
iCLASS® is a proprietary, ISO 15693 compliant, 13.56 MHz contactless product line developed by HID Corporation (an industry-leading card and reader manufacturer).

Smart card system offers a high level of security and data integrity through the use of high-level cryptographic techniques. The memory of the MIFARE DESFire™ EV1 with PACSA credential is divided into several sectors (also called application areas). Each sector is secured by an Authentication Key. A reader can only access a secure sector after a successful mutual authentication is performed. A successful mutual authentication requires that the reader and the card share a common secret – the mutual authentication key. The size of the mutual authentication key employed by the MIFARE DESFire™ EV1 with PACSAsmart card system is 128 bits – the largest in the industry. After a successful authentication has taken place between the reader and the credential, communication is authorized and the reader gains access to the authenticated sector or application using Message Authentication Codes (MACs). Each message going back and forth between the reader and the credential is digitally signed, ensuring that the communication remains authentic at all times and that an unauthorized device cannot interfere with the communication between the credential and the reader. Smart card system is the only ISO14443 access control system offering Message Authentication Coding (MAC). Smart card system also offers encryption of the data stored on the credential. The encryption algorithms employed by the PACSA is AES, which is a strong, proven algorithms.

A smart card is a piece of plastic, the same size as a credit or debit card, with a silicon chip embedded in it. The chip contains a microprocessor, which is a miniature computer which can perform calculations and store data in its memory.
These chips hold a variety of information, from stored (monetary)-value used for retail and vending machines, to secure information and applications for higher-end operations such as medical/health care records. New information and/or applications can be added depending on the chip capabilities.
The card is “smart” because it is “active”, that is that it can receive information, process it and then “make a decision”. For example, when a smart card is inserted in a terminal, the terminal sends its “digital signature” to the microprocessor. If the digital signature agrees with the existing parameters in the processor’s memory, then the memory files are opened and the data made visible to the terminal. In the same way, the card sends its “digital signature” to the terminal and the terminal’s microprocessor verifies it. This mutual verification is done off-line, this means that the terminal is not connected to the system’s central computer, known as the host. The verification process typically takes a fraction of a second. In addition to digital signatures, Personal Identification Numbers (PIN) and hand written signatures can be used.

 Where did the word smart card come from?

The French, of course. While inventors in the U.S., Japan and Austria, were issued patents that pre-date those of Frenchman Roland Moreno, it was the French who put up big money to push the technology. They did this in the 1970′s, during a period of major national investment in modernizing the nation’s technology infrastructure. The first company to make major R&D investments in the technology was Bull which holds about 60 patents related to micro processor (MP) cards.
Cards were original none as “Carte a memoire” or memory card. In 1980, when France began a major campaign to export the technology, the Roy Bright of the government’s marketing organization Intelimatique coined the word “Smart Card.”


MIFARE DESFire EV1 contactless multi-application IC
If this rollback is necessary, it is done without user interaction before carrying out further commands. To ensure data integrity on application level, a transaction-oriented backup is implemented for all file types with backup. It is possible to mix file types with and without backup within one application. As the commands are the same for MF3ICD81, MF3ICD41 and MF3ICD21, the command details are available in Ref. 1. Only the memory size is different between the three devices.

Available file types
The files within an application can be any of the following types:
Standard data files Backup data files Value files with backup Linear record files with backup Cyclic record files with backup

The 7 byte UID is fixed, programmed into each device during production. It cannot be altered and ensures the uniqueness of each device. The UID may be used to derive diversified keys for each ticket. Diversified MIFARE DESFire EV1 keys contribute to gain an effective anti-cloning mechanism and increase the security of the original key see Ref. 6. Prior to data transmission a mutual three pass authentication can be done between MIFARE DESFire EV1 and PCD depending on the configuration employing either 56-bit DES (single DES, DES), 112-bit DES (triple DES, 3DES), 168-bit DES (3 key triple DES, 3K3DES) or AES. During the authentication the level of security of all further commands during the session is set. In addition the communication settings of the fileapplication result in the following options of secure communication between MIFARE DESFire EV1 and PCD: MF3ICD40)  backwards-compatible mode to MF3ICD40: 4 byte MAC, all other authentications based on DES3DESAES: 8 byte CMAC backwards-compatible mode to MF3ICD40: A 16-bit CRC is calculated over the stream and attached. The resulting stream is encrypted using the chosen cryptographic method. All other authentications based DES3DESAES: A 32-bit CRC is calculated over the stream and attached. The resulting stream is encrypted using the chosen cryptographic method. Find more information on the security concept of the product in Ref. 1. Be aware not all levels of security are recommended. The recommended secure handling of the product can be seen in Ref. 2 and in Ref. 10.

MIFARE DESFire EV1 contactless multi-application IC
DESFire command set
Table 4. Command REQA WUPA ANTICOLLISIONSELECT Cascade Level 1 ISOIEC 14443-3 Description REQA and ATQA are implemented fully according to ISOIEC 14443-3 WUPA is implemented fully according to ISOIEC 14443-3 ANTICOLLISION and SELECT commands are implemented fully according to ISOIEC 14443-3 the response is part 1 of the UID ANTICOLLISION and SELECT commands are implemented fully according to ISOIEC 14443-3 the response is part 2 of the UID brings MIFARE DESFire EV1 to the HALT state ANTICOLLISIONSELECT Cascade Level 2

ISOIEC 14443-4
Table 5. Command RATS PPS ISOIEC 14443-4 Description identifies the MIFARE DESFire EV1 type to the PCD allows individual selection of the communication baud rate between PCD and MIFARE DESFire EV1 for DESFire it is possible to set different communication baud rates for each direction i.e. DESFire allows a non-symmetrical information interchange speed. if the MIFARE DESFire EV1 needs more time than the defined FWT to respond to a PCD command it requests a Waiting Time eXtension (WTX) allows MIFARE DESFire EV1 to be brought to the HALT state WTX DESELECT

MIFARE DESFire EV1 contactless multi-application IC, Table 6. Command Authenticate Security related commands Description MIFARE DESFire EV1 and the reader device show in an encrypted way that they possess the same secret which especially means the same key this not only confirms that both entities are permitted to perform operations on each other but also creates a session key which can be used to keep the further communication path secure as the name “session key” implicitly indicates, each time a new authentication procedure is successfully completed a new key for further cryptographic operations is generated changes the master key settings on MIFARE DESFire EV1 and application level configures the card and pre-personalizes the card with a key, defines if the UID or the random ID is sent back during communication setup and configures the ATS string changes any key stored on the MIFARE DESFire EV1 reads out the current key version of any key stored on the MIFARE DESFire EV1 Change KeySettings Set Configuration Change Key Get Key Version Remark: All command and data frames are exchanged between MIFARE DESFire EV1 and PCD by using block format as defined in ISOIEC 14443-4.

Table 7. Command Create Application Delete Application Get Applications IDs Free Memory GetDFNames Get KeySettings Level commands Description creates new applications on the MIFARE DESFire EV1 permanently deactivates applications on the MIFARE DESFire EV1 returns the Application IDentifiers of all applications on a MIFARE DESFire EV1 returns the free memory available on the card returns the DF names gets information on the MIFARE DESFire EV1 and application master key settings in addition it returns the maximum number of keys which are configured for the selected application selects one specific application for further access releases the MF3ICD81 user memory returns manufacturing related data of the MIFARE DESFire EV1 returns the UID Select Application FormatMF3ICD81 Get Version GetCardUID Remark: All command and data frames are exchanged between MIFARE DESFire EV1 and PCD by using block format as defined in ISOIEC 14443-4.

MIFARE DESFire EV1 contactless multi-application IC ,Table 8. Command Get FileIDs Get FileSettings Change FileSettings Create StdDataFile Create BackupDataFile Create ValueFile Create LinearRecordFile Application level commands Description returns the File IDentifiers of all active files within the currently selected application gets information on the properties of a specific file changes the access parameters of an existing file creates files for the storage of plain unformatted user data within an existing application on the MIFARE DESFire EV1 creates files for the storage of plain unformatted user data within an existing application on the MIFARE DESFire EV1, additionally supporting the feature of an integrated backup mechanism creates files for the storage and manipulation of 32-bit signed integer values within an existing application on the MIFARE DESFire EV1 creates files for multiple storage of similar structural data, for example, loyalty programs within an existing application on the MIFARE DESFire EV1 once the file is filled completely with data records, further writing to the file is not possible unless it is cleared creates files for multiple storage of similar structural data, for example, logging transactions within an existing application on the MIFARE DESFire EV1 once the file is filled completely with data records, the MIFARE DESFire EV1 automatically overwrites the oldest record with the latest written one (this wrap is fully transparent for the PCD) permanently deactivates a file within the file directory of the currently selected application Create CyclicRecordFile DeleteFile
Remark: All command and data frames are exchanged between MIFARE DESFire EV1 and PCD by using block format as defined in ISOIEC 14443-4.

Table 9. Command Read Data Write Data Get Value Credit Debit Limited Credit Write Record Read Records Data manipulation commands Description reads data from Standard Data files or Backup Data files writes data to Standard Data files or Backup Data files reads the currently stored value from Value files increases a value stored in a Value file decreases a value stored in a Value file allows a limited increase of a value stored in a Value file without having full Credit permissions to the file writes data to a record in a Cyclic or Linear Record file reads out a set of complete records from a Cyclic or Linear Record file.

MIFARE DESFire EV1 contactless multi-application IC

1. General description
MIFARE DESFire EV1 is ideal for service providers wanting to use multi-application smart cards in transport schemes, eGovernment or identity applications. It fully complies with the requirements for fast and highly secure data transmission, flexible memory organization and interoperability with existing infrastructure. MIFARE DESFire EV1 is based on open global standards for both air interface and cryptographic methods. It is compliant to all 4 levels of ISOIEC 14443A and uses optional ISOIEC 7816-4 commands. Featuring an on-chip backup management system and the mutual three pass authentication, a MIFARE DESFire EV1 card can hold up to 28 different applications and 32 files per application. The size of each file is defined at the moment of its creation, making MIFARE DESFire EV1 a truly flexible and convenient product. Additionally, an automatic anti-tear mechanism is available for all file types, which guarantees transaction oriented data integrity. With MIFARE DESFire EV1, data transfer rates up to 848 kbits can be achieved, allowing fast data transmission. The main characteristics of this device are denoted by its name DESFire EV1: DES indicates the high level of security using a 3DES hardware cryptographic engine for enciphering transmission data and Fire indicates its outstanding position as a fast, innovative, reliable and secure IC in the contactless proximity transaction market. Hence, MIFARE DESFire EV1 brings many benefits to end users. Cardholders can experience convenient contactless ticketing while also having the possibility to use the same device for related applications such as payment at vending machines, access control or event ticketing. In other words, the MIFARE DESFire EV1 silicon solution offers enhanced consumer-friendly system design, in combination with security and reliability. MIFARE DESFire EV1 delivers the perfect balance of speed, performance and cost efficiency. Its open concept allows future seamless integration of other ticketing media such as smart paper tickets, key fobs, and mobile ticketing based on Near Field Communication (NFC) technology. It is also fully compatible with the existing MIFARE reader hardware platform. MIFARE DESFire EV1 is your ticket to contactless systems worldwide.

MIFARE DESFire EV1 contactless multi-application IC
2. Features
2.1 Key features

3. Applications
I I I I I Advanced public transportation High secure access control Event ticketing eGovernment Identity
2 KB and 4 KB versions are also available.

MIFARE DESFire EV1 contactless multi-application IC
4. Quick reference data
Min 14.96
Typ 13.56 17.0
Max 19.04
Unit MHz pF
EEPROM characteristics tret Nendu(W) tcy(W)
retention time write endurance write cycle time
year cycle ms
Stresses above one or more of the values may cause permanent damage to the device. Exposure to limiting values for extended periods may affect device reliability. Measured with LCR meter.
5. Ordering information

1 This package is also known as MOA4.
Type number
Version -
SOT500-2 SOT500-2 SOT500-2

MIFARE DESFire EV1 contactless multi-application IC
6. Block diagram
Fig 1.
Block diagram of MF3ICD81, MF3ICD41, MF3ICD21
7. Limiting values
Table 3. Limiting values 12 In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol II Ptotpack Tstg Tamb VESD Ilu
Parameter input current total power dissipation per package storage temperature ambient temperature electrostatic discharge voltage latch-up current
Min -55 -25
Max 30 200 125 70 -
MIFARE DESFire EV1 contactless multi-application IC
8. Functional description
8.1 Contactless energy and data transfer
In the MIFARE system, the MIFARE DESFire EV1 is connected to a coil consisting of a few turns embedded in a standard ISOIEC smart card (see Ref. 7). A battery is not needed. When the card is positioned in the proximity of the PCD antenna, the high speed RF communication interface allows data to be transmitted up to 848 kbits.
8.2 Anti-collision
An intelligent anti-collision mechanism allows more than one MIFARE DESFire EV1 in the field to be handled simultaneously. The anti-collision algorithm selects each MIFARE DESFire EV1 individually and ensures that the execution of a transaction with a selected MIFARE DESFire EV1 is performed correctly without data corruption resulting from other MIFARE DESFire EV1s in the field.
8.3 UIDserial number
The unique 7 byte (UID) is programmed into a locked part of the NV memory which is reserved for the manufacturer. Due to security and system requirements these bytes are write-protected after being programmed by the IC manufacturer at production time. According to ISOIEC 14443-3 (see Ref. 11) during the first anti-collision loop the cascade tag returns a value of 88h and also the first 3 bytes of the UID, UID0 to UID2 and BCC. The second anti-collision loop returns bytes UID3 to UID6 and BCC. SN0 holds the manufacturer ID for NXP (04h) according to ISOIEC 14443-3 and ISOIEC 7816-6 AMD 1. MIFARE DESFire EV1 also allows Random ID to be used. In this case MIFARE DESFire EV1 only uses a single anti-collision loop. The 3 byte random number is generated after RF reset of the MIFARE DESFire EV1.
8.4 Memory organization
The 248 KB NV memory is organized using a flexible file system. This file system allows a maximum of 28 different applications on one MIFARE DESFire EV1. Each application provides up to 32 files. Every application is represented by its 3 bytes Application IDentifier (AID). Five different file types are supported see Section 8.5. A guideline to assign DESFire AIDs can be found in the application note MIFARE Application Directory (MAD) see Ref. 8. Each file can be created either at MIFARE DESFire EV1 initialization (card productioncard printing), at MIFARE DESFire EV1 personalization (vending machine) or in the field. If a file or application becomes obsolete in operation, it can be permanently invalidated. Commands which have impact on the file structure itself (e.g. creation or deletion of applications, change of keys) activate an automatic rollback mechanism, which protects the file structure from being corrupted.

Protocol Configuration Register

13.56MHz MIFARE Reader Module

Protocol Configuration Register

Protocol Configuration Register (05h)        
Bit 8 (MSB) Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 (LSB)
reserved reserved reserved Cont. Mode BinaryTim eout ExtendID Binary AutoStart

Extend ID: Extend TAG ID (serial number)

0 (factory default) The TAG ID Byte is not transmitted before the serial number 1 TAG ID Byte is transmitted before the serial number

This setting does only affect the commands continuos reading (‘c’), select (‘s’) and MultiTagSelect (‘m’).

If set a the unique serial number (4 bytes) of the transponder is extended by a single prefix byte. The values for the prefix byte are:

0×01 denotes a MIFARE® Light Transponder (not supported) 0×02 denotes a MIFARE® Standard Transponder 0×03 denotes a MIFARE® Pro Transponder 0xFF denotes a unknown Transponder

Binary: binary mode flag

0 (factory default) reader operates in ASCII protocol mode 1 reader operates in binary protocol mode


0 reader is in command mode at start up 1(factory default) reader executes the command ‘c’ (read serial numbers continuously) at start up automatically. In binary protocol mode this bit is ignored (The binary protocol does not support continuos reading).


0 (factory default) Binary Time-out disabled. 1 Binary Time-out enabled.

This flag is only interpreted if the reader operates in binary mode. If the serial bus stays idle for more than 96 ms (no data is transmitted), the reader will clear its command buffer ant enter “Command Read” mode. “Command Read” mode means that the reader is waiting for valid data frames (beginning with the STX code).

Example: You transmit the sequence “02h 00h FFh “ to a third party module (a door opener, turnstile control unit, …). Since this sequence starts with a valid Mifare reader protocol but does not terminate properly, the Mifare reader would wait infinitely. Termination can be enforced using the binary timeout.  

Cont. Mode (continuous read mode)

0 (factory default) continuous reading does only support single tags continuous reading does support multiple tags

Using single tag reading is much faster than using multiple tag reading. If in single mode more than one card is in the field the reader does transmit none or only one of the serial numbers (depending on reading conditions and transponder positioning).

Baud Rate

Baud Rate Selection (06h)          
Bit 8 (MSB) Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 (LSB)
reserved reserved reserved reserved reserved reserved BS1 BS0

BS1, BS0:

BS1 BS0 Baudrate

0 0 9600 baud (factory default)

0 1 19200 baud

1 0 38400 baud

1 1 57600 baud

Communication is always 8 data bits, no parity, 1 stop bit. At delivery the Communication speed is set to 9600 baud.

To take over changes in any of these register the reader must be reset. It is recommended to clear reserved bits for ensure compatibility with further firmware versions.


r05 reads block 4 (sector 1)
00112233445566778899AABBCCEEDD FF reply from reader if Mifare® Standard block 5 contains “001122…”
r00 reads Manufacturer Code (sector 0)
rv04 reads value of block 4
00112233 reply from reader if Mifare® Standard value block 4 contains “00112233”
re04 reads register 4 (Station ID)
01 reply if Station ID is set to 01
re05 reads register 5 (Protocol Configuration)
01 reply if Protocol Configuration register is set to 01
re06 reads register 6 (Baud Rate Selection)
03 reply if baudrate is set to 57600 baud