RIGOL MSO/DS1000Z Series - Manual (Page 173)

Chapter 8 Protocol Decoding RIGOL
MSO1000Z/DS1000Z User’s Guide 8-11
Wherein, there are even number of 1 in the 8-bit data 01111101 and the check
bit should be 1; but the check bit detected on the TX is 0, thus check error
occurs.
Note: Two error marks will be displayed when end frame error and check error
are detected at the same time.
(01111101, LSB)
Frame End Error
The check bit detected is 0
Frame Check Error