Abstract Command-Response Card Object¶

Abstract Command-Response Card object.

This header defines an abstract interface used to communicate with an Integrated Circtuit Card (either with contacts or contactless) using request-response frames. Each frame is a request and should generate some response frame or a timeout. Example of such a card is ISO/IEC 14443 Proximity Integrated Circuit Card or ISO/IEC 7816 Integrated Circuit Card exchanging command-response pairs using T=0 or T=1 protocol.

For now only synchronous API is defined. Async API may be added later if needed.

Macro functions (Pcd)

Convenience macros for easy calling of ‘member functions’

crcardTransceive(inst, tx_buf_p, tx_buf_size, resp_size_p)¶

See: CRCardVMT.transceive

crcardGetResponseSize(inst)¶

See: CRCardVMT.getResponseSize

crcardGetResponse(inst, buf_p, max_buf_size)¶

See: CRCardVMT.getResponse

Enums

enum crcard_result_t¶

Operation result codes.

Values:

CRCARD_OK¶: Transmission successful, received response

CRCARD_TX_ERROR¶: Unrecoverable transmission errror

CRCARD_RX_ERRPR¶: Unrecoverable reception error

CRCARD_TIMEOUT¶: Transmission successful, no response

CRCARD_NONEXISTENT¶: Card removed, no further comm possible

struct CRCardVMT¶

#include <hal_abstract_CRCard.h>

Abstract CRCard Virtual Method Table.

Note: use macros defined in this file to call these functions for convenience. Name of the macro is the same as a name of this function with crcard prefix.

Public Members

crcard_result_t (*transceive)(void *inst, uint8_t *tx_buffer, uint16_t tx_buffer_size, uint16_t *response_size)¶

Send a frame of data to a card and wait for a response.

The response will be stored in a response buffer. Invoking this function will clear contents of the response buffer, if any.

Return

Operation result

Parameters

inst: Pointer to a CRCard structure
tx_buffer: Data to send
tx_buffer_size: Number of bytes to send
response_size: Number of bytes received

uint16_t (*getResponseSize)(void *inst)¶

Get number of remaining bytes in the response buffer.

Return

Number of bytes in the response buffer

Parameters

inst: Pointer to a CRCard structure

uint16_t (*getResponse)(void *inst, uint8_t *data, uint16_t buffer_size)¶

Retrieves a response from the response buffer.

Think of the response buffer as a queue. When this function is called no more than buffer_size bytes are removed from this queue and copied to data buffer.

Function getResponseSize returns number of bytes in this queue.

Return

Number of copied bytes

Parameters

inst: Pointer to a CRCard structure
data: Buffer to copy the response to
buffer_size: Maximum number of bytes to copy

struct CRCard¶

#include <hal_abstract_CRCard.h>

Base Command-Response Card.

This class represents a generic Command-Response Card.

Public Members

const struct CRCardVMT *vmt¶: Virtual Methods Table

void *data¶: Private data of a driver