KeyBoard_QT/docs/host_dri_rebuild.md

Host DRI Rebuild

Goal

Keep the device runtime layer small and transport-only.

The DRI layer should:

• enumerate endpoints
• open and close connections
• read raw bytes
• write raw bytes

The DRI layer should not:

• parse frames
• manage protocol state
• decide handshake success

Completed Nodes

Node 1: GATT placeholder

Files:

• KeyBorad/KeyBorad/DRI/GATT/Dri_Gatt.h
• KeyBorad/KeyBorad/DRI/GATT/Dri_Gatt.cpp

Design notes:

• reserves the BLE transport position early
• keeps the implementation small for now
• avoids mixing GATT transport with logic concerns

Implemented behavior:

• keep the same surface shape as CDC:
  • Enum
  • Open
  • Close
  • ReadBytes
  • WriteBytes
• stay transport-only
• keep real BLE implementation for a later node

Node 2: BLE device discovery

Files updated in this step:

• KeyBorad/KeyBorad/DRI/GATT/Dri_Gatt.cpp
• KeyBorad/KeyBorad/KeyBorad.vcxproj

Design notes:

• use Qt Bluetooth directly
• keep discovery synchronous for now so the first teaching step stays small
• only collect low-energy devices

Implemented behavior:

• start BLE discovery with QBluetoothDeviceDiscoveryAgent
• collect device name and address
• filter to LowEnergyCoreConfiguration
• stop after a short timeout

Node 3: GATT open and raw byte transport

Files updated in this step:

• KeyBorad/KeyBorad/DRI/GATT/Dri_Gatt.h
• KeyBorad/KeyBorad/DRI/GATT/Dri_Gatt.cpp

Design notes:

• keep transport-only responsibility
• use Qt Bluetooth instead of custom Win32 BLE code
• connect, discover service, subscribe, then pass raw bytes upward

Implemented behavior:

• connect to a BLE device by address
• discover the target custom service
• resolve RX/TX characteristics
• enable notify on TX
• queue raw bytes from TX notify
• write raw bytes to RX characteristic

Node 4: CDC transport cleanup

Files updated in this step:

• KeyBorad/KeyBorad/DRI/Dri_Cdc.h
• KeyBorad/KeyBorad/DRI/Dri_Cdc.cpp

Design notes:

• remove frame parsing from the driver
• remove handshake ownership from the driver
• keep only enumerate/open/close/read-bytes/write-bytes

Implemented behavior:

• list ports with Dri_Cdc_Enum()
• open one port with Dri_Cdc_Open()
• close one port with Dri_Cdc_Close()
• read raw bytes with timeout
• write raw bytes with timeout

Next DRI nodes

• implement real GATT discovery and notify/write path
• provide one simple connection summary for logic layer