Biometrics include architecture

flowchart LR
  Host[niseCore sensor and PAL] --> Core[vcsfw_v4 core protocol]
  Host --> Priv[private and parameter extensions]
  Host --> Fido[FIDO operations]
  Host --> Test[module-test commands]
  Host --> Tune[clock / WOVAR tuning]
  Host --> Identity[USB and flexible device IDs]
  Core --> Wire[Packed command / reply ABI]
  Priv --> Wire
  Fido --> Wire
  Test --> Wire
  Tune --> Wire
  Wire --> Firmware[Fingerprint sensor firmware]
  Identity -. selects device behavior .-> Host

Boundaries

Component	Source	Architectural responsibility
Core protocol	vcsfw_v4.h	Defines firmware command IDs and primary packed command/reply structures.
Private/parameter extensions	vcsfw_v4priv.h	Defines private parameters for capture, finger detect, calibration, WOF/WOVAR, clocks and sensor-specific behavior.
FIDO operations	vcsfw_v4fido.h	Defines firmware-side FIDO operation IDs and payload contracts.
Module test	vcsfw_v4moduletest.h	Defines module-test command contracts.
Clock/tuning	vcsfw_v4clocktune.h and vcsfw_v4wovar.h	Defines clock tuning and wake-on-variance controls.
VIP/extended tags	vcsfw_v4vip.h and vcsfw_extag.h	Defines additional command/tag namespaces.
Device identity	usbid.h and flexid.h	Maps hardware/device identities used by host components.
Whitney commands	whitney_commands.h	Adds Whitney-family command definitions.

Change-safety rules

• Follow calls and data across component boundaries; a changed header or customer property can affect multiple binaries.
• Keep source revision and branch explicit because configured branches differ substantially.
• Validate both the component and its direct consumers.
• Treat optional/customer-selected components as conditional, not universally deployed.