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DEVELOPING A USB SMARTCARD READER WITH ST7SCR

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void CRD_StartWaitingTime(void)

This function starts the Waiting Timer. The bWaitingTimeFlag software flag is set by an inter-

rupt when the count is finished. For more information, please refer to the crd.h file.

This counter is used by the ICC level functions to determine the end of the transmission.

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void CRD_StopWaitingTime(void)

This function stops the Waiting Timer and resets the corresponding flag.

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void CRD_WaitingTime(unsigned long WaitingTimeInEtu)

This function creates a wait loop for WaitingTimeInEtu. The waiting time is:

– WaitingTimeInEtu * Etu

dure. The Etu value is set by the CRD_SetEtu function.

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void CRD_InitReceive(unsigned int ReceiveBufSize, unsigned char * pBuffer)

This function will configure the CRD for reception and begin the process.

– pBuffer is the address of the buffer where the data will be copied.

– ReceiveBufSize is the size of the buffer.

If the ICC transmits more bytes than the number specified in the ReceiveBufSize variable,

data saving is stopped and a flag is set. This reception is done entirely by interrupt processing.

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unsigned int CRD_NumberOfBytesReceived(void)

This function returns the number of bytes already received during the reception process.

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unsigned int CRD_EndReceive(void)

This function stops the reception process and returns the number of bytes received and

copied in the buffer.

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void CRD_InitTransmit(unsigned int TransmitBufSize, unsigned char * pBuffer)

This function configures the CRD for transmission and begins the process.

– pBuffer is the address of the buffer containing the data to be transmitted.

– TransmitBufSize is the number of bytes to be transmitted.

This transmission is entirely done by interrupt processing.

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unsigned int CRD_NumberOfBytesToTransmit(void)

This function returns the remaining number of bytes to be transmitted.