Motorola ColdFire MCF5281 - Manual (Page 354)

Fast Ethernet Controller (FEC)
17-44 Freescale Semiconductor
17.5.15.2.3 CRC Error
When a CRC error occurs with no dribble bits, FEC closes the buffer and sets RxBD[CR]. CRC checking
cannot be disabled, but the CRC error can be ignored if checking is not required.
17.5.15.2.4 Frame Length Violation
When the receive frame length exceeds MAX_FL bytes the BABR interrupt is generated, and RxBD[LG]
is set. The frame is not truncated unless the frame length exceeds 2047 bytes.
17.5.15.2.5 Truncation
When the receive frame length exceeds 2047 bytes, frame is truncated and RxBD[TR] is set.
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3