Each bit of this value set to '1' indicates a specific status condition in this DSU, or a fault or status condition in its associated CSU. Octets are numbered in the order in which they appear in the PDU. Bits are numbered from the most-significant leftmost bit in the octet (bit 0) to the least-significant rightmost bit (bit 7). Cajun numbering continues across octets, so that octet 1 bit 0 is called bit 8 in the Cajun scheme. That number is also shown below, with the octet value for each single bit set. If the CSU is reporting a Blue Alarm (AIS), multiple other alarms may be hidden by the Blue Alarm. Octets 0-1 show CSU fault status. Octet 2 shows CSU loopbacks active. Octet 3 shows DSU loopbacks active. Cajun Octet Octet bit# bit# value Meaning 0-5 0/0-5 Unused. 6 0/6 0x02 CSU CRC multiframe lost (LCM) - E1 only 7 0/7 0x01 CSU remote multiframe alignment lost (RMA) - E1 only 8 1/0 0x80 CSU local multiframe alignment lost (LMA) - E1 only 9 1/1 0x40 CSU polar density violations (PDV) - in the T1 configuration using AMI line coding, this is equivalent to bipolar violations (BPV). 10 1/2 0x20 CSU alarm indication signal (AIS, Blue Alarm). 11 1/3 0x10 CSU remote alarm indication signal (RAI, Yellow Alarm). 12 1/4 0x08 CSU loss of frame (LOF, Red Alarm) - unable to synchronize 13 1/5 0x04 CSU excessive error rate (EER) - applies to ESF framing only. on DS1 signal. 14 1/6 0x02 CSU out of frame (OOF) - 2 of 4 frame synchronization bits in error. 15 1/7 0x01 CSU loss of signal (LOS) - 175 consecutive zeroes received. 16-20 2/0-4 Unused. 21 2/5 0x04 CSU Digital diagnostic loopback active (towards DTE). This is the equivalent of either equipment (DTE) or repeater loopback in the Paradyne 3160. 22 2/6 0x02 CSU Line loopback active (towards network). 23 2/7 0x01 CSU Payload loopback active (towards network). 24-26 3/0-2 Unused. 27 3/3 0x10 DSU Far-end Data Channel loopback active. 28 3/4 0x08 DSU Data Terminal loopback active. 29 3/5 0x04 DSU Remote loopback active. 30 3/6 0x02 DSU Near-end Data Channel loopback active. 31 3/7 0x01 DSU Local DTE loopback active.