You can find the words written in grey in the diagram in my source code as jump mark.
The yellow part wait for a preample.
Then pretest waits for „0“ to begin to read the first byte.
Set the indirect register to the first byte and read bit by bit 8 times.
If the 9th bit is „0“ then read in next byte.
If the 9th bit is „1“ then jump to EXOR.