Chips › Processors › 6502 family › WDC 65816

WDC 65816

1984

WDC's 1984 16-bit successor to the 6502, powering the Apple IIGS and the Super Nintendo's CPU.

Emulators

EmulatorTypeLicenseSite
Apple IIgs (KEGS)onlineGPL-3.0Website ↗
BizHawkdownloadableMIT
GSplusdownloadableGPL-2.0
GSportdownloadableGPL-2.0
KEGSdownloadableGPL-2.0
MednafendownloadableGPL-2.0
MesendownloadableGPL-3.0
Mesen2downloadableGPL-3.0
NESboxonlineMIT
OpenEmudownloadableBSD-3-Clause
ProvenancedownloadableBSD-3-Clause
RetroArchbothGPL-3.0
SNES (LakeSnes)onlineMITWebsite ↗
Snes9xdownloadableNon-commercial
Sweet16downloadableFreeware
ZSNESdownloadableGPL-2.0
aresdownloadableISC
bsnesdownloadableGPL-3.0
higandownloadableGPL-3.0
nemulatordownloadableFreeware
no$snsdownloadableFreeware

Machines

Apple IIGS

Super NES

Super NES Jr

Reference & documentation

External technical references for programming WDC 65816 and for writing emulators.

ResourceTypeNotes
WDC W65C816S Official Datasheet ↗DatasheetCanonical WDC datasheet: electrical, timing, cycle-by-cycle tables
undisbeliever 65816 Opcodes Reference ↗Instruction setAll opcodes, cycle counts, flags, pseudocode
The 6502/65C02/65C816 Instruction Set Decoded ↗Instruction setaaabbbcc opcode encoding structure explained
Defence-Force 65816 Opcode Table ↗Instruction setAlphabetical opcode list with timings, compatibility notes
WDC W65C816S Datasheet (pinout) ↗PinoutPin descriptions: VDA, VPA, VPB, MLB signals
Programming the 65816 (Eyes & Lichty) ↗ProgrammingDefinitive assembly programming manual, full PDF
6502.org 65C816 Opcodes Tutorial ↗ReferenceAddressing modes, mode combinations, boundary-wrap rules
Super Famicom Wiki 65816 Reference ↗ReferenceRegisters, flags, 110 instructions with examples
Notes on the WDC 65c816 ↗ReferenceEmulator-author gotchas: REP/SEP bug, edge cases
SingleStepTests 65816 Test Suite ↗Test suiteJSON per-opcode tests with cycle-accurate bus activity