package i6502 import ( "fmt" ) type Instruction struct { OpType // Embed OpType Op8 byte // 8-bit operand for 2-byte instructions Op16 uint16 // 16-bit operand for 3-byte instructions Address uint16 // Address location where this instruction got read, for debugging purposes } // Return a string containing debug information about the instruction and operands. func (i Instruction) String() (output string) { switch i.Size { case 1: output = fmt.Sprintf("~~~ 0x%04X: 0x%02X - %s [%s] {%d}\n", i.Address, i.Opcode, instructionNames[i.opcodeId], addressingNames[i.addressingId], i.Cycles) case 2: output = fmt.Sprintf("~~~ 0x%04X: 0x%02X - %s 0x%02X [%s] {%d}\n", i.Address, i.Opcode, instructionNames[i.opcodeId], i.Op8, addressingNames[i.addressingId], i.Cycles) case 3: output = fmt.Sprintf("~~~ 0x%04X: 0x%02X - %s 0x%04X [%s] {%d}\n", i.Address, i.Opcode, instructionNames[i.opcodeId], i.Op16, addressingNames[i.addressingId], i.Cycles) } return }