Functional Requirements Overview

Functional Requirements Overview

Document Information

Field	Value
Project	ViceSharp
Version	0.1.0-draft
Last Updated	2026-07-08
Status	Draft

Purpose

This document serves as the master index for all ViceSharp Functional Requirements (FRs). FRs define observable, testable emulator behavior. Classic VICE documentation is used as the source corpus for emulator-visible FR behavior; Vice-Sharp architecture documents constrain TRs and implementation boundaries.

Index scope note (2026-07-08): The tables below are a hand-maintained snapshot frozen at the 2026-05-13 requirement set. FRs added after 2026-05 (for example FR-TICKHIST-001, FR-IECMON-001, FR-DRVTRUE-001, FR-SNDREG-001, FR-PACESEL-001, FR-SIDAUDIO-001) are managed in the MCP requirements store; the generated wiki export (PublishWiki target) is the authoritative, complete FR index. Interface names in the traceability matrix reflect the original 2026-05 design vocabulary and may predate the implemented ViceSharp.Abstractions surface; consult the generated TR-per-FR wiki export for the authoritative mapping. Do not hand-extend the tables below; register new FRs through the MCP requirements store.

FR Document Index

Document	Subsystem	FR Range
FR-Audio-SID.md	Audio (SID)	FR-SID-001 .. FR-SID-014
FR-CPU-Emulation.md	CPU	FR-CPU-001 .. FR-CPU-005
FR-Cartridges.md	Cartridges	FR-CRT-001 .. FR-CRT-005
FR-Configuration-Resources.md	Configuration / Resources	FR-CFG-001 .. FR-CFG-008
FR-Host-UI-Boundary.md	Host / UI Boundary	FR-HOST-001 .. FR-UI-004
FR-IO-CIA.md	I/O (CIA 6526)	FR-CIA-001 .. FR-CIA-007
FR-IO-VIA.md	I/O (VIA 6522)	FR-VIA-001 .. FR-VIA-005
FR-Input.md	Input Devices	FR-INP-001 .. FR-INP-006
FR-Machine-Profiles.md	Machine Profiles	FR-PRF-001 .. FR-PRF-008
FR-Media-Capture.md	Media Capture	FR-MED-001 .. FR-MED-005
FR-Memory-System.md	Memory	FR-MEM-001 .. FR-MEM-006
FR-Monitor.md	Machine Monitor	FR-MON-001 .. FR-MON-006
FR-Performance.md	Runtime Performance	FR-PERF-RUNFRAME-001
FR-Snapshot.md	Snapshot / Replay	FR-SNP-001 .. FR-SNP-004
FR-Storage-Drives.md	Disk Drives	FR-DRV-001 .. FR-DRV-006
FR-Storage-Tape.md	Tape / Datasette	FR-TAP-001 .. FR-TAP-005
FR-Video-VIC-II.md	Video (VIC-II)	FR-VIC-001 .. FR-VIC-010

Traceability Matrix -- FR to Interface to Iteration

FR ID	Title	Primary Interface(s)	Iteration
FR-CFG-001	Resource File and Command-Line Configuration	IEmulatorSession, IConfigurationStore, HostControlService	2
FR-CFG-002	ROM and Romset Selection	IArchitectureDescriptor, IRomProvider, HostControlService	1
FR-CFG-003	Palette Selection and Color Resource Handling	IVideoChip, IFrameSink, HostStateService	2
FR-CFG-004	Hotkey Configuration and Action Dispatch	UiHostClient, HostControlService, HostMediaService, HostMonitorService	2
FR-CFG-005	Autostart and Program Launch Handling	HostMediaService, HostInputService, HostControlService, IAutostartService	2
FR-CFG-006	Host-Backed Peripheral Resource Configuration	IConfigurationStore, HostControlService, HostStateService	3
FR-CFG-007	RAM Initialization and Debug Resource Behavior	IMachine, ISnapshotManager, HostStateService	3
FR-CFG-008	Performance Limiter Configuration	HostControlService, HostStatusService, IClockedDevice	1
FR-CIA-001	CIA Timer A and Timer B with Cascade Mode	ICia, ITimer	1
FR-CIA-002	Time-of-Day Clock	ICia, ITodClock	1
FR-CIA-003	Keyboard Matrix Scanning via CIA1	ICia, IKeyboardMatrix	1
FR-CIA-004	Joystick Port Reading via CIA1	ICia, IJoystickPort	1
FR-CIA-005	CIA Serial Port Shift Register	ICia, ISerialPort	2
FR-CIA-006	NMI Generation from CIA2	ICia, IInterruptController	1
FR-CIA-007	IRQ Generation from CIA1	ICia, IInterruptController	1
FR-CPU-001	Full 6502/6510 Instruction Set Including Undocumented Opcodes	ICpu, IInstructionDecoder	0
FR-CPU-002	Cycle-Accurate Execution Timing	ICpu, IClockedDevice	0
FR-CPU-003	Interrupt Handling with Correct Timing	ICpu, IInterruptController	0
FR-CPU-004	6510 I/O Port at Addresses $0000/$0001	ICpu, IMemoryMappedDevice	0
FR-CPU-005	8502 2MHz Mode Support for C128	ICpu, IClockController	3
FR-CRT-001	Standard 8K and 16K Cartridge Support	ICartridgePort, IAddressSpace	2
FR-CRT-002	Ocean Type 1 Bank-Switching Cartridge	ICartridgePort	2
FR-CRT-003	EasyFlash Cartridge with Flash Memory	ICartridgePort, IFlashMemory	3
FR-CRT-004	Action Replay and Retro Replay Cartridge	ICartridgePort	3
FR-CRT-005	Final Cartridge III (FC3)	ICartridgePort	3
FR-DRV-001	Commodore 1541 Single Floppy Disk Drive Emulation	IDiskDrive, IClockedDevice	2
FR-DRV-002	Commodore 1571 Double-Sided Floppy Disk Drive Emulation	IDiskDrive, IClockedDevice	3
FR-DRV-003	Commodore 1581 3.5" Floppy Disk Drive Emulation	IDiskDrive	3
FR-DRV-004	Group Code Recording Encoding and Decoding	IDiskDrive, IGcrCodec	2
FR-DRV-005	IEC Serial Bus Protocol	ISerialBus, IDiskDrive	2
FR-DRV-006	Fast Loader Compatibility	IDiskDrive, ISerialBus	3
FR-HOST-001	Host-Owned Emulator Session Lifecycle	IEmulator, IMachine, IArchitectureDescriptor, HostControlService	1
FR-HOST-002	Host-Mediated Disk, Tape, and Cartridge Attachment	IDiskDrive, ITapeUnit, ICartridgePort, HostMediaService	2
FR-HOST-003	Host-Streamed Video Frames for Remote UI Clients	IFrameSink, HostOutputService, VideoService	1
FR-HOST-004	Host-Normalized Keyboard, Joystick, and Machine Control	IKeyboardMatrix, IJoystickPort, IInputSource, HostInputService, HostControlService	1
FR-HOST-005	Host-Owned Snapshot, Screenshot, and Diagnostic Operations	ISnapshotManager, IMediaCapture, IMonitor, HostStateService	1
FR-HOST-006	Host Runtime Status and Control Telemetry	HostControlService, HostStatusService, IMachine, ICpu, IClockedDevice	1
FR-INP-001	Keyboard Matrix Emulation	IKeyboardMatrix	1
FR-INP-002	Joystick Port 1 and Port 2 Emulation	IJoystickPort	1
FR-INP-003	Commodore 1351 Proportional Mouse Emulation	IMousePort	2
FR-INP-004	Lightpen Input	ILightpenPort, IVideoChip	3
FR-INP-005	Paddle Controller Input	IPaddlePort	3
FR-INP-006	VICE VKM Keymap Selection and Real-Time Keyboard Translation	IKeyboardInputMap, IKeyboardInputMapSelection, IKeyboardMatrix, IMachineKeyboardInput, HostInputService	1
FR-MED-001	Screenshot Capture (PNG/BMP)	IMediaCapture	1
FR-MED-002	Video Recording (MP4 via FFmpeg)	IMediaCapture, IVideoEncoder	2
FR-MED-003	Audio Recording (WAV/FLAC)	IMediaCapture, IAudioEncoder	2
FR-MED-004	Synchronized Audio/Video Capture	IMediaCapture, IMuxer	2
FR-MED-005	Output Format Selection and Configuration	IMediaCapture	2
FR-MEM-001	Address Decoding and PLA Banking Configuration	IAddressSpace, IBankController	0
FR-MEM-002	RAM Under ROM Access	IAddressSpace	0
FR-MEM-003	Ultimax Cartridge Mode	IAddressSpace, ICartridgePort	2
FR-MEM-004	VIC-II Bank Switching via CIA2	IAddressSpace, IVicBankSelector	1
FR-MEM-005	Color RAM ($D800-$DBFF)	IAddressSpace	1
FR-MEM-006	Zero Page and Stack Page Behavior	IAddressSpace	0
FR-MON-001	Real-Time Disassembly View	IMonitor, IDisassembler	1
FR-MON-002	Memory Hex and ASCII Display	IMonitor	1
FR-MON-003	Breakpoint Management	IMonitor, IBreakpointManager	1
FR-MON-004	CPU Register Inspection and Manipulation	IMonitor, ICpu	1
FR-MON-005	Memory Bank View Selection	IMonitor, IAddressSpace	2
FR-MON-006	Watch Expressions	IMonitor	2
FR-PERF-RUNFRAME-001	C64 PAL RunFrame Throughput	IMachine, IClock, IBus, IVideoChip, IAudioChip	1
FR-PRF-001	Commodore 64 (Original NMOS) Machine Profile	IMachineProfile	1
FR-PRF-002	Commodore 64C Machine Profile	IMachineProfile	2
FR-PRF-003	Commodore SX-64 Machine Profile	IMachineProfile	2
FR-PRF-004	Commodore 128 Machine Profile	IMachineProfile	3
FR-PRF-005	Commodore VIC-20 Machine Profile	IMachineProfile	3
FR-PRF-006	Commodore PET Machine Profile	IMachineProfile	4
FR-PRF-007	Commodore Plus/4 Machine Profile	IMachineProfile	4
FR-PRF-008	Commodore C16 Machine Profile	IMachineProfile	4
FR-SID-001	Three Independent Voice Oscillators	IAudioChip, IVoice	1
FR-SID-002	Waveform Generation (Triangle, Sawtooth, Pulse, Noise)	IAudioChip, IWaveformGenerator	1
FR-SID-003	Combined Waveform Output	IAudioChip, IWaveformGenerator	2
FR-SID-004	6581 SID Filter Emulation	IAudioChip, IFilter	1
FR-SID-005	8580 SID Filter Emulation	IAudioChip, IFilter	2
FR-SID-006	ADSR Envelope Generator	IAudioChip, IEnvelopeGenerator	1
FR-SID-007	Ring Modulation	IAudioChip, IVoice	2
FR-SID-008	Hard Sync (Oscillator Synchronization)	IAudioChip, IVoice	2
FR-SID-009	Noise Waveform Linear Feedback Shift Register	IAudioChip, IWaveformGenerator	1
FR-SID-010	Direct Digital Sample Playback via Volume Register	IAudioChip	2
FR-SID-011	External Audio Input	IAudioChip	3
FR-SID-012	Dual-SID (Stereo SID) Configuration	IAudioChip, IAddressSpace	3
FR-SID-013	SID Audio Backend Wiring	IAudioChip, IAudioBackend	2
FR-SID-014	VICE-Compatible Signed SID Voice Output and Demo Pacing	IAudioChip, IAudioBackend	1
FR-SNP-001	Save Complete Machine State to Snapshot	ISnapshotManager	1
FR-SNP-002	Load Machine State from Snapshot	ISnapshotManager	1
FR-SNP-003	Deterministic Input Replay	ISnapshotManager, IReplayEngine	2
FR-SNP-004	Snapshot Comparison and State Diffing	ISnapshotManager	3
FR-TAP-001	Datasette Motor Control	ITapeUnit	2
FR-TAP-002	TAP File Format Support (v0 and v1)	ITapeUnit, ITapCodec	2
FR-TAP-003	Cycle-Accurate Tape Read Timing	ITapeUnit, IClockedDevice	2
FR-TAP-004	Tape Write Support	ITapeUnit	3
FR-TAP-005	Turbo Tape Loader Compatibility	ITapeUnit	3
FR-UI-001	Dockable Host UI Control Client	UiHostClient, HostControlService, HostOutputService, HostInputService, AvaloniaRenderSurface	1
FR-UI-002	Emulator Status and Machine Control Bar	UiHostClient, HostControlService, HostStatusService	1
FR-UI-003	Collapsible Tabbed Emulator Sidebar	UiHostClient, HostMediaService, HostInputService, HostControlService	1
FR-UI-004	Docked and Pop-Out Monitor Control	IMonitor, HostMonitorService, UiHostClient	1
FR-VIA-001	VIA 6522 Timer A and Timer B Operation	IVia, ITimer	3
FR-VIA-002	VIA Shift Register	IVia	3
FR-VIA-003	VIA Port A and Port B with Handshake Protocols	IVia	3
FR-VIA-004	VIC-20 VIA Integration (VIA1 and VIA2)	IVia, IAddressSpace	3
FR-VIA-005	Disk Drive VIA Integration (1541/1571)	IVia, IDiskDrive	3
FR-VIC-001	Raster Engine with PAL/NTSC Timing	IVideoChip, IClockedDevice	1
FR-VIC-002	Character Display Modes (Standard, Multicolor, ECM)	IVideoChip	1
FR-VIC-003	Bitmap Display Modes (Standard, Multicolor)	IVideoChip	1
FR-VIC-004	Sprite Engine (8 Hardware Sprites)	IVideoChip, ISpriteUnit	1
FR-VIC-005	Sprite Collision Detection	IVideoChip, ISpriteUnit	1
FR-VIC-006	Badline Handling and CPU DMA Cycle Stealing	IVideoChip, IClockedDevice	1
FR-VIC-007	Border Behavior Including Open Border Tricks	IVideoChip	2
FR-VIC-008	Flexible Line Interpretation (FLI) Support	IVideoChip	2
FR-VIC-009	VIC-II Bank Switching (See also FR-MEM-004)	IVideoChip, IVicBankSelector	1
FR-VIC-010	Sprite Multiplexing DMA Timing	IVideoChip, ISpriteUnit	2

Source Corpus

• Primary FR source corpus: native/vice/vice/doc.
• Detailed source inventory: docs/requirements/sources/VICE-Source-Manifest.md.
• Current x64sc parity backfill coverage: docs/requirements/backfill/X64SC-Requirement-Coverage.md.
• Required x64sc model selector/profile matrix: docs/requirements/backfill/X64SC-Model-Matrix.md.
• Technical and test requirements are derived from Vice-Sharp architecture and verification strategy, not from VICE implementation choices.