diff --git a/Source/Core/DSPCore/Src/DspIntLoadStore.cpp b/Source/Core/DSPCore/Src/DspIntLoadStore.cpp index 6834500cae..82bc101c66 100644 --- a/Source/Core/DSPCore/Src/DspIntLoadStore.cpp +++ b/Source/Core/DSPCore/Src/DspIntLoadStore.cpp @@ -26,32 +26,25 @@ namespace DSPInterpreter { // SRS @M, $(0x18+S) // 0010 1sss mmmm mmmm -// Store value from register $(0x18+S) to a memory pointed by address M. -// (8-bit sign extended). -// ALTERNATIVELY: It now seems that the upper 8 bits are controlled -// by CR, not sign extension. -// FIXME: Perform additional operation depending on destination register. +// Move value from register $(0x18+D) to data memory pointed by address CR[0-7] | M. +// That is, the upper 8 bits of the address are the bottom 8 bits from CR, and the +// lower 8 bits are from the 8-bit immediate. // Note: pc+=2 in duddie's doc seems wrong void srs(const UDSPInstruction& opc) { u8 reg = ((opc.hex >> 8) & 0x7) + 0x18; -// u16 addr = (u16)(s16)(s8)opc.hex; u16 addr = (g_dsp.r[DSP_REG_CR] << 8) | (opc.hex & 0xFF); dsp_dmem_write(addr, g_dsp.r[reg]); } // LRS $(0x18+D), @M // 0010 0ddd mmmm mmmm -// Move value from data memory pointed by address M (8-bit sign -// extended) to register $(0x18+D). -// ALTERNATIVELY: It now seems that the upper 8 bits are controlled -// by CR, not sign extension. -// FIXME: Perform additional operation depending on destination register. -// Note: pc+=2 in duddie's doc seems wrong +// Move value from data memory pointed by address CR[0-7] | M to register $(0x18+D). +// That is, the upper 8 bits of the address are the bottom 8 bits from CR, and the +// lower 8 bits are from the 8-bit immediate. void lrs(const UDSPInstruction& opc) { u8 reg = ((opc.hex >> 8) & 0x7) + 0x18; - //u16 addr = (u16)(s16)(s8)opc.hex; u16 addr = (g_dsp.r[DSP_REG_CR] << 8) | (opc.hex & 0xFF); g_dsp.r[reg] = dsp_dmem_read(addr); }