txc-03456 TranSwitch Corporation, txc-03456 Datasheet - Page 12

• Manufacturer Part Number: txc-03456
• Description: Device Level Mapper
• Manufacturer: TranSwitch Corporation

RECEIVE AND TRANSMIT OVERHEAD COMM CHANNEL INTERFACE
EXTERNAL TIMING FOR ADD BUS
Symbol
ROCHC
ROCHD
Symbol
TOCHC
TOCHD
EXTC
EXC1
Pin No.
Pin No.
107
125
105
97
5
6
I/O/P
I/O/P
O
O
O
I
I
I
TTL4mA
TTL4mA
TTL4mA
Type
Type
TTL
TTL
TTL
Transmit Overhead Comm Channel Clock: An output clock
provided for sourcing the transmit overhead communications
channel data ("O"-bits). This clock has an effective data trans-
fer rate of 720 kHz (8 kHz per bit, times 90 bits).
Transmit Overhead Comm Channel Data: Data is clocked in
on positive transitions of the clock signal (TOCHC). The data is
unaligned in relationship to the overhead communications
channel data bit placement in the SDH/SONET format.
Receive Overhead Comm Channel Clock: A clock provided
for outputting the transmit overhead communications channel
data. This clock has an effective data transfer rate of 720 kHz
(8 kHz per bit, times 90 bits).
Receive Overhead Comm Channel Data: Data is clocked
out on negative transitions of the clock signal (ROCHC). The
data output for the overhead communications channel from the
format is unaligned in relationship with the SDH/SONET
frame.
External Clock Input: Enabled by placing a high on the
ENABT lead (pin 36). Used for deriving output timing for the
add bus. A clock rate of 19.44 MHz is required for AU-4/
STS-3c operation. This clock input is monitored for loss of
clock.
External C1 Input: Enabled by placing a high on the ENABT
lead (pin 36). An optional C1 input signal that can be used for
frame alignment. In addition, an option is provided for the
pointer tracking feature which can compensate up to a frame
in offset delay. If this pin is not used, it should be grounded.
DATA SHEET
- 12 -
Name/Function
Name/Function
Ed. 1A, January 2000
TXC-03456
TXC-03456-MB
L4M