dolphin_write64
Write a 64-bit big-endian value to PowerPC memory in Dolphin for atomic updates of paired 32-bit slots or doubles.
Instructions
PURPOSE: Write an unsigned 64-bit big-endian value to PowerPC memory. USAGE: For paired 32-bit slots, doubles, packed flags. Atomic from the game's perspective; preferred over chaining two write32s when ordering matters. BEHAVIOR: DESTRUCTIVE: overwrites eight bytes with no undo. Address MUST be 8-byte aligned. value is a DECIMAL STRING (0..18446744073709551615) to preserve precision past JS's 2^53 number limit.
GameCube + Wii main address space landmarks (PowerPC, big-endian): 0x80000000-0x817FFFFF MEM1 main RAM (24 MiB) — GameCube + Wii game code & data GameCube games stay entirely within MEM1. Wii games use MEM1 for code and frequently-accessed data. 0x80000020 OS_GLOBALS — game-info struct (disc ID, FST, etc.) 0x80000034 OS_ARENA_LO (start of free MEM1 heap) 0x80003100 OS_REPORT (developer-console mirror, varies by SDK) 0x90000000-0x93FFFFFF MEM2 (64 MiB) — Wii ONLY. Larger texture/asset data, IOS work areas. Reading MEM2 on a GameCube game returns garbage / FAIL. 0xCC000000-0xCC00FFFF Hollywood I/O (Wii) / Flipper I/O (GameCube) — DMA, GPU FIFO, AI, EXI registers. Reads are usually safe, writes can wedge the emulator. Avoid. 0xCD000000-0xCD007FFF Wii-only Hollywood registers.
Notes: • All multi-byte values are BIG-ENDIAN on the real hardware. Felk's memory.read_u*/write_u* helpers handle the byte swap for you — the value you see is the value the game sees as a u32. • Addresses are 32-bit; Felk truncates the high bits of any u64 address argument. • Pointers in MEM1 are often stored as 4-byte addresses with the high bit set (e.g. 0x81234567). Dereferencing them requires no masking — pass the raw value back into memory.read_*.
RETURNS: 'Wrote VAL_DEC (0xVAL_HEX) → ADDR_HEX'.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| address | Yes | Absolute PowerPC virtual address (0x80000000-0x9FFFFFFF). Pass as a number; hex literals like 0x80001000 are fine. Reads 8 consecutive bytes starting here and interprets them as a big-endian value. MUST be 8-byte aligned (address % 8 === 0). PowerPC raises an alignment exception on misaligned access in hardware, but Dolphin's emulated bus is forgiving and silently returns the aligned-down word — i.e. you get the bytes from address & ~7, not what you asked for. For unaligned multi-byte reads use dolphin_read_range and assemble client-side. Useful ranges: 0x80000000-0x817FFFFF for MEM1 (GC + Wii), 0x90000000-0x93FFFFFF for MEM2 (Wii only). | |
| value | Yes | 64-bit value as a non-negative DECIMAL STRING. Range 0..18446744073709551615 (2^64 - 1). For signed, encode as two's complement. |