Logical host interfaces

On top of the physical host interfaces and transport layers, the SpringCore devices support a wide variety of communication protocols or Logical host interfaces.

The primary Logical host interface protocol is selected by configuration the Profile configuration register.

Host protocol implementation matrix

Some of the Logical interfaces are not available on every Physical and Transport interfaces for technical reasons, or because they make no senses on all communication medium. The table below summarizes the implementation matrix.

USB BLE Network Serial
Direct Protocol Yes Yes TCP Server
MQTT Client
No
CCID Protocol (PC/SC) Yes Yes TCP Server
MQTT Client
No
HID Protocol (RFID Scanner) Yes Yes No No
$SCRDR Protocol Over CDC No TCP Server
MQTT Client
Yes
SpringProx Legacy Protocol Over CDC No No Yes

Secondary host protocol

The Profile configuration register specifies the overall behavior of the SpringCore device, and therefore its primary Logical host interface protocol, but the physical host interface and transport layer may allow a second Logical host interface to be used in the same time.

  • For USB, the SpringCore device exposes a compound device profile. Whatever the primary Logical protocol, the Direct Protocol remains available as the secondary USB interface, unless this feature is disabled in the USB options configuration register,
  • For BLE, the SpringCore device exposes a GATT with more than one service. The Direct Protocol is exposed as a secondary service in the GATT, unless this feature is disabled in the BLE options configuration register.