I have tried to test it, but something does not work. I have not the same crc checksum for some reason. I have not adapted the slave code in the same way as the master, but normally that should not make any difference to receive the data on the master side only. Where could be the problem? I really have read up and down my code I have posted in #19, but I will not see where the problem is 
The crc checksum is made the same way as the sent one, so this should work. Any help?