FCC HDLC Controller
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 36-17
Table36-10 describes FCCS bits.

Table36-10. FCCS Register Field Descriptions

Bits Name Description
0–4 Reserved, should be cleared.
5 FG Flags. While FG is cleared, each time a new bit is received the most recently received 8 bits are
examined to see if a flag is present. FG is set as soon as an HDLC flag (0x7E) is received on the
line. Once FG is set, it remains set at least 8 bit times while the next 8 bits of input data are
examined. If another flag occurs, FG stays set for at least another eight bits. Otherwise, FG is
cleared and the search begins again.
0HDLC flags are not currently being received.
1HDLC flags are currently being received.
6 Reserved, should be cleared.
7 ID Idle status. ID is set when the RXD signal is a logic one for 15 or more consecutive bit times; it is
cleared after a logic zero is received.
• 0 The line is busy.
• 1 The line is idle.