public static void execute(ARM7TDMI cpu, MemoryInterface memory, int opcode) {
int rdIndex = (opcode >>> 8) & 0x0007;
int spValue = cpu.getSP();
int offset = (opcode & 0x00FF) << 2;
if ((opcode & 0x0800) == 0) { // STR Rd, [SP, #nn]
memory.storeWord(spValue + offset, cpu.getRegister(rdIndex));
} else { // LDR Rd, [SP, #nn]
cpu.setRegister(rdIndex, memory.loadWord(spValue + offset));
}
}
