Datasheet
DS26518 8-Port T1/E1/J1 Transceiver
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9.9.4 Signaling
The DS26518 supports both software and hardware-based signaling. Interrupts can be generated on changes of
signaling data. The DS26518 is also equipped with receive-signaling freeze on loss of synchronization (OOF),
carrier loss or change of frame alignment. The DS26518 also has hardware pins to indicate signaling freeze.
Features include the following:
• Flexible signaling support:
Software or hardware based
Interrupt generated on change of signaling data
Receive-signaling freeze on loss of frame, loss of signal, or change of frame alignment
• Hardware pins for carrier loss and signaling freeze indication
Table 9-17. Registers Related to Signaling
REGISTER
FRAMER 1
ADDRESSES
FUNCTION
Transmit-Signaling Registers 1 to 16
(
TS1 to TS16)
140h to 14Bh (T1/J1)
140h to 14Fh (E1 CAS)
Transmit ABCD signaling.
Software-Signaling Insertion Enable
Registers 1 to 4 (
SSIE1 to SSIE4)
118h, 119h, 11Ah, 11Bh
When enabled, signaling is inserted for
the channel.
Transmit Hardware-Signaling Channel
Select Registers 1 to 4
(
THSCS1 to THSCS4)
1C8h, 1C9h, 1CAh, 1CBh
Bits determine which channels will have
signaling inserted in hardware-signaling
mode.
Receive-Signaling Control Register
(
RSIGC)
013h Freeze control for receive signaling.
Receive-Signaling All-Ones Insertion
Registers 1 to 3
(
T1RSAOI1 to T1RSAOI3)
038h, 039h, 03Ah
Registers for all-ones insertion (T1 mode
only).
Receive-Signaling Registers 1 to 16
(
RS1 to RS16)
040h to 04Bh (T1/J1)
040h to 04Fh (E1)
Receive-signaling bytes.
Receive-Signaling Status Registers 1
to 4 (
RSS1 to RSS4)
098h to 09Ah (T1/J1)
98h to 9Fh (E1)
Receive-signaling change of status bits.
Receive-Signaling Change of State
Enable Registers 1 to 4 (
RSCSE1 to
RSCSE4)
0A8h, 0A9h, 0AAh, 0ABh
Receive-signaling change of state
interrupt enable.
Receive Latched Status Register 4
(
RLS4)
093h Receive-signaling change of state bit.
Receive Interrupt Mask Register 4
(
RIM4)
0A3h
Receive-signaling change of state
interrupt mask bit.
Receive-Signaling Reinsertion Enable
Registers 1 to 4 (
RSI1 to RSI4)
0C8h, 0C9h, 0CAh, 0CBh Registers for signaling reinsertion.
Note: The addresses shown above are for Framer 1. Addresses for Framers 2 to 8 can be calculated using the following: Framer n = (Framer 1
address + (n - 1) x 200hex); where n = 2 to 8 for Framers 2 to 8.