ds2156gn Maxim Integrated Products, Inc., ds2156gn Datasheet - Page 62

• Manufacturer Part Number: ds2156gn
• Description: Ds2156, Ds2156l, Ds2156ln T1/e1/j1 Single-chip Transceiver Tdm/utopia Ii Interface
• Manufacturer: Maxim Integrated Products, Inc.

9. E1 FRAMER/FORMATTER CONTROL AND STATUS REGISTERS
The E1 framer portion of the DS2156 is configured by a set of four control registers. Typically, the
control registers are only accessed when the system is first powered up. Once the DS2156 has been
initialized, the control registers need only to be accessed when there is a change in the system
configuration. There are two receive control registers (E1RCR1 and E1RCR2) and two transmit control
registers (E1TCR1 and E1TCR2). There are also four status and information registers. Each of these eight
registers is described in this section.
9.1
Register Name:
Register Description:
Register Address:
Bit #
Name
Default
Bit 0/Resync (RESYNC). When toggled from low to high, a resync is initiated. Must be cleared and set again for a
subsequent resync.
Bit 1/Sync Enable (SYNCE)
Bit 2/Frame Resync Criteria (FRC)
Bit 3/Receive CRC4 Enable (RCRC4)
Bit 4/Receive G.802 Enable (RG802). See Section 16 for details.
Bit 5/Receive HDB3 Enable (RHDB3)
Bit 6/Receive Signaling Mode Select (RSIGM)
Bit 7/RSER Control (RSERC)
E1 Control Registers
0 = auto resync enabled
1 = auto resync disabled
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
0 = CRC4 disabled
1 = CRC4 enabled
0 = do not force RCHBLK high during bit 1 of time slot 26
1 = force RCHBLK high during bit 1 of time slot 26
0 = HDB3 disabled
1 = HDB3 enabled
0 = CAS signaling mode
1 = CCS signaling mode
0 = allow RSER to output data as received under all conditions
1 = force RSER to 1 under loss-of-frame alignment conditions
RSERC
7
0
RSIGM
E1RCR1
E1 Receive Control Register 1
33h
6
0
RHDB3
5
0
RG802
4
0
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RCRC4
3
0
FRC
2
0
SYNCE
1
0
RESYNC
0
0