TMXF28155/51 Super Mapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
Preliminary Data Sheet
May 2001
524
Agere Systems Inc.
21 28-Channel Framer Block Functional Description
(continued)
Parallel Bus System Interface Mode.
This interface consists of a 17-bit wide parallel bus operating at
19.44 Mbits/s, 9 bits of which form a byte of data and a data parity bit while the other 8 bits contain the signaling
and control information. A clock and frame sync are expected in both the receive and transmit directions. For a
28-link device, only 1/3 of the bytes are populated. In the transmit direction the unpopulated bytes are 3-stated,
while in the receive direction they are ignored. Three 28-link devices (Super Mappers) can be connected in parallel
to the telecom bus for implementing an STS-3 (STM-1) rate interface.
Note:
The Tx system is defined as the interface that sends data out of the chip and toward the system (non-
SONET) interface. The Rx system receives data from the system. These designations are opposite of the
path definitions for the Super Mapper.
21.26.2 System Interface References/Standards
I
ITU G.783 characteristics of synchronous digital hierarchy (SDH) equipment functional blocks.
I
ITU Q.511 exchange interfaces towards other exchanges.
21.26.3 Transmit/Receive System Interface Features
The features supported in the system interface are summarized below:
I
Data rates of 2.048 Mbits/s, 4.096 Mbits/s, 8.192 Mbits/s, and 19.44 Mbyte/s.
I
Clock rates of 2.048 MHz, 4.096 MHz, 8.192 MHz, 16.384 MHz, and 19.44 MHz.
I
A global input clock and frame sync (CHI and parallel bus system interface modes).
I
Byte offset
—
2.048 Mbits/s, 0
—
31 bytes.
I
Byte offset
—
4.096 Mbits/s, 0
—
63 bytes.
I
Byte offset
—
8.192 Mbits/s, 0
—
127 bytes.
I
Bit offset (CHI mode).
I
1/2-bit offset (CHI mode).
I
1/4-bit offset (CHI CMS mode).
I
Clock mode select (CMS) (CHI mode).
I
Associated signaling mode (ASM) (CHI mode).
I
Double time slot mode, CHIDTS (CHI mode).
I
Double NOTFAS system time slot, FRM_DNOTFAS (
Table 347
) (CHI and parallel bus system interface modes).
I
Sampled clock edge for transmit system frame sync (CHI mode).
I
Global programmable stuffed time slot position in DS1 mode (CHI mode).
I
Global programmable stuffed byte in DS1 mode (CHI and parallel bus system interface modes).
I
Global single time slot loopback address for system or line.
I
Programmable automatic system AIS (loss of frame alignment).
I
Programmable automatic system AIS (CEPT CRC-4 multiframe alignment timer expiration).
I
On-demand transmission of system AIS.
I
Programmable even/odd parity generation (parallel bus system interface mode).
21.26.4 Double NOTFAS System Time-Slot (FRM_DNOTFAS (
Table 347
)) Mode
This mode is applicable to the CHI and parallel bus system interface modes. In the default case
(FRM_DNOTFAS = 0 (
Table 347
)), both the FAS and NOTFAS time slots are transmitted by the transmit system
interface and expected by the receive system interface.