Host Protocols CCID Protocol (PCSC)

April 13, 2023 at 2:39 AM

SpringCore CCID implementation

The implementation is a subset of the USB CCID 1.10 specification.

It operates with

  • A PC to RDR (host to device) endpoint for commands (BulkOut),
  • A RDR to PC (device to host) endpoint for responses (BulkIn),
  • A second RDR to PC (device to host) endpoint for notifications (InterruptIn).

CCID_PC_To_RDR Commands

Code Command Description Equivalent PC/SC function
62 PC_To_RDR_IccPowerOn Power up the card in the slot, and return its ATR SCardConnect
63 PC_To_RDR_IccPowerOff Power down the card in the slot SCardDisconnect
65 PC_To_RDR_GetSlotStatus Retrieve the slot’s current status and protocol data SCardStatus
6B PC_To_RDR_Escape Send a direct command to the device SCardControl
6F PC_To_RDR_XfrBlock Send a C-APDU to the card (and return its R-APDU) SCardTransmit

CCID_RDR_To_PC Responses

Code Command Description In response to
80 RDR_To_PC_DataBlock R-APDU returned by the card
ATR of the card		 PC_To_RDR_XfrBlock (success)
PC_To_RDR_IccPowerOn (success)
81 RDR_To_PC_SlotStatus Status of the slot PC_To_RDR_GetSlotStatus
PC_To_RDR_IccPowerOff
PC_To_RDR_XfrBlock (failure)
PC_To_RDR_IccPowerOn (failure)
83 RDR_To_PC_Escape Send a direct command to the device PC_To_RDR_Escape

Non-USB implementations

SpringCore devices also support a variant of the USB CCID protocol on Serial and Network (TCP) interfaces.

On such interfaces, the Control endpoint, that is implicit for USB devices, has no equivalent. A specific Non-USB Control implementation emulates this missing feature.

Also, to ease the host-side implementation of the protocol, the format of the notification messages (going though InterruptIn message) has been adapted to have the very same header as response messages. This is documented in the Non-USB Notifications paragraph.