You have the right idea.  NEC specified the device, subdevice, and function numbers are to be sent with the least significant bit of each byte first.  The hexadecimal numbers you've posted probably don't follow that rule, but 00 and FF are the same regardless of bit order. The function number needed for IrScrutinizer is  likely to be 0x02 rather than 0x40.  BTW, you don't need to convert to decimal, IrScrutinizer will accept hex numbers if you enter them with a preceding 0x.