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DEVELOPING A USB SMARTCARD READER WITH ST7SCR

– Slot_No_Error

– SlotError_HW_Error

– SlotError_ICC_Mute

Note: At the end of this function, the CRD is in Manual mode.

s

void ICC_ResetAsync(void)

This function executes a warm reset sequence in compliance with ISO 7816 specifications for

asynchronous ICCs.

Note: At the end of this function, the CRD is in Manual mode.

s

unsigned char ICC_GetAtrAsync(unsigned char Voltage, unsigned char *

pReceiveBuffer, unsigned int * pAtrSize)

This function executes the Power-on or Reset sequence and answer to reset reading for an

asynchronous ICC. The “voltage” variable can be:

– CRD_Voltage18V (for 1.8 volts)

– CRD_Voltage3V (for 3.0 volts)

– CRD_Voltage5V (for 5.0 volts)

Note: The “voltage” variable is used only if the slot status is inactive at the beginning of the

function. In this case, the cold Answer to Reset (ATR) is returned. If the ICC is already active,

a simple reset is generated and a warm ATR is returned.

– pReceiveBuffer is the address of the buffer to fill with the ATR.

– pAtrSize is the address of the data containing:

– Input: the size of the ReceiveBuffer in bytes.

– Output: the length of the ATR written in the ReceiveBuffer in bytes.

This function returns one of the following error codes:

– Slot_No_Error

– SlotError_HW_Error

– SlotError_ICC_Mute

– SlotError_BAD_ATR_TS

– SlotError_XFR_Overrun

s

unsigned char ICC_SendCommandAsync(unsigned char * pTransmitBuffer,

unsigned int CommandSize, unsigned char ProtocolType)

This function sends a packet of bytes to the ICC with the Guard Time currently in use.

– pTransmitBuffer is the address of the buffer containing the data to be sent.