CT_init, CT_data, CT_close — Functions to handle communication
with integrated circuit cards and cardterminals
unsigned short ctn,
unsigned short pn);
unsigned short ctn,
unsigned char * dad,
unsigned char * sad,
unsigned short lenc,
unsigned char * command,
unsigned short * lenr,
unsigned char * response);
unsigned short ctn);
This manual page describes the CT-API functions used to handle
communication with integrated circuit cards and cardterminals. The CT-
API functions are generic, and allows the use of memory cards (often
referred as synchronous cards) and processor cards (often referred as
The CT-API implementation is dependent on the cardterminal that is
used. For each cardterminal a CT-API library implementation should be
provided, either by the manufacturer or by third parties. This manpage
is not a complete specification of the CT-API, but a general overview
of the most common functionalities.
CT_init() selects and initializes the interface with the cardterminal
(f.i. serial port, USB bus, or any other type of connector). The
CT_init() function must be called before communicating with the card or
the cardterminal. A unique cardterminal number chosen by the caller is
assigned by the CT-API library to the initialized connection.
ctn Cardterminal number: identifies the connection with the
cardterminal for further references. It’s chosen by the
caller of the function.
pn Port number: selects the physical interface. The port number
assignment is dependent on the CT-API implementation. However
most serial cardterminal implementations use the convention
of assigning the value 0 to the first serial port, 1 to the
second serial port and so on. See the file
/usr/include/ctapi.h of your CT-API implementation for a list
of allowed values.
CT_data() sends a command to the card or to the cardterminal and
returns the response to the calling program.
ctn Cardterminal number: the number specified in CT_init()
call for this cardterminal.
dad Destination address. If the command is sent to the
cardterminal, it must point to a variable containing the
value CT (0x01). If the command is sent to a card, the
destination address variable must be set to the number
identifying the slot of the cardterminal where the card is
inserted, ranging from ICC1 (0x00) and ICC2 (0x02) to ICC14
On the return of the response, the variable pointed by dad is
set to the value HOST (0x02) or REMOTE_HOST (0x05).
sad Source address. When the function is called it is usually set
to point to a variable with the value HOST (0x02), although
the value REMOTE_HOST (0x05) may ocurr in some applications
if the CT-API implementation supports remote calls.
On the return of the response, the variable pointed by sad is
set to any of the values from CT (0x01), ICC1 (0x00), ICC2
(0x02) to ICC14 (0x0E).
lenc Command length in bytes.
command Pointer to the buffer that conveys the command to be sent to
the card or cardterminal.
lenr Before function call, pointer to a variable containig the
maximum buffer size in bytes for the response data. After
successful function call it contains the size in bytes of the
response Pointer to the response data. Memory buffer of at least the
size in bytes specified in lenr must be allocated before
calling to the function.
CT_close() terminates the communication with the cardterminal which has
been assigned to a logical cardterminal number by the function
CT_init(). The function shall be called for each initialized
cardtreminal before the end of the program in order to free resources
ctn Cardterminal number: as specified in CT_init()
call for this cardterminal.
CT_init(), CT_data(), and CT_close() functions return a value
of type char.
OK Function call was successful.
Invalid parameter or value.
ERR_CT Cardterminal Error. The cardterminal is temporarily not
accessible (busy with other or internal processes). The
problem can be solved by the application.
ERR_TRANS Transmission Error. Transmission errors due to mechanical,
electrical or protocol failures. Reset of the cardterminal is
Memory assignment error. A memory error occurred (f.i. the
allocated buffer is too small for the returned data).
ERR_HTSI Host Transport Service Interface error. Commonly returned if
the error is produced by the software layer and not in the
communication with the hardware.
The MKT (Multifunktionale KartenTerminals) specifications, available
for download from Teletrust website http://www.teletrust.de (link to
URL http://www.teletrust.de) . In special the documents:
Part 3: CT-API. Cardterminal Applications Programming Interface.
Part 4: CT-BCS. Cardterminal Basic Command Set.
Part 7: IC cards with synchronous transmission Part3: Usage of
ISO/IEC 7816: Identification cards - Integrated circuit(s) cards with
Part 4: Interindustry commands for interchange.
This manual page was written by Carlos Prados <email@example.com>.