Datasheet

DS26521 Single T1/E1/J1 Transceiver

130 of 258

RCR1 (E1 Mode)

Receive Control Register 1

081h

Bit # 7 6 5 4 3 2 1 0

Name — RHDB3 RSIGM RG802 RCRC4 FRC SYNCE RESYNC

Default 0 0 0 0 0 0 0 0

Note: This register has an alternate definition for T1 mode. See RCR1.

Bit 6: Receive HDB3 Enable (RHDB3).

0 = HDB3 disabled

1 = HDB3 enabled (decoded per O.162)

Bit 5: Receive-Signaling Mode Select (RSIGM).

0 = CAS signaling mode

1 = CCS signaling mode

Bit 4: Receive G.802 Enable (RG802). See

Figure 10-23 for details.

0 = do not force RCHBLK high during bit 1 of time slot 26

1 = force RCHBLK high during bit 1 of time slot 26

Bit 3: Receive CRC-4 Enable (RCRC4).

0 = CRC-4 disabled

1 = CRC-4 enabled

Bit 2: Frame Resync Criteria (FRC).

0 = resync if FAS received in error three consecutive times

1 = resync if FAS or bit 2 of non-FAS is received in error three consecutive times

Bit 1: Sync Enable (SYNCE).

0 = auto resync enabled

1 = auto resync disabled

Bit 0: Resynchronize (RESYNC). When toggled from low to high, a resynchronization of the receive-side framer is

initiated. Must be cleared and set again for a subsequent resync.