We have just launched a short 6 minute video tutorial for AnalysIR introducing the use of the Checksum Calculator feature in AnalysIR, which is available via YouTube. The tutorial covers the steps to verify the position and type of checksums that are typically found in Air Conditioner infrared signals. The types of checksums covered include:
- …for both bytes and nibbles.
By comparing the output of the calculator for all of the above Checksum/CRC methods, it is easy to solve one of the hardest tasks in reverse engineering AC IR signals. For the more challenging signals it is possible to restrict certain bytes within the signal from the calculation. A common example would be to exclude the last byte of the signal from the calculation, as this is where it is usually stored. Another common trap is the bit order within the bytes of a signal. AnalysIR can automatically adjust the bit order between MSB, LSB & LSB8. LSB8, where the bits in each byte are reversed, is the most common ordering for AC signals.
AnalysIR Video Tutorial Checksum Calculator