tdat04622 ETC-unknow, tdat04622 Datasheet - Page 8

• Manufacturer Part Number: tdat04622
• Description: Tdat Sonet/sdh 155/622/2488 Mbits/s Data Interfaces
• Manufacturer: ETC-unknow

for Version 1 and 1A of the Device
Path Terminator (PT)
PT3. Remote Defect Indicator (RDI) Behavior
The SONET standards require that when an RDI changes value, it should hold the value for a minimum of
20 frames. This applies to a no error state, which should be maintained for at least 20 consecutive frames.
However, it is also intended by the SONET standard that the occurrence of an error state should be reported
immediately.
TDAT042G5 responds to error conditions within 100 ms (ANSI
erated or removed within 100 ms of detecting or terminating an incoming defect), in which case the two require-
ments become functionally the same.
Single-bit and enhanced RDI behave differently under the following conditions:
I
I
The single-bit error RDI does not hold the no error state for 20 frames. However, the enhanced RDI does hold the
no error state for 20 consecutive frames.
Workaround
No workaround is available for this condition.
Corrective Action
The enhanced RDI indicator in future versions of the device will behave the same as the single-bit error indicator.
PT4. SS Pointer Interpretation Algorithm
The SDH standards do not require that the SS bits are set to binary 10 for SDH equipment. The SS bit values are
not used in determining a valid pointer value. Because of this, the SS pointer interpretation algorithm is not imple-
mented in the device. Bit 5 (RSSPTRNORM[A—D]) of PT control registers 0x0AA6, 0xAAE, 0x0AB6, and 0x0ABE
is not used. Bits 1 and 0 (RSSEXP[1:0]) of PT provisioning register 0x0AC7 are not used.
Workaround
No workaround is available for this condition.
Corrective Action
These bits will be removed from the PT registers in future revisions of the advance data sheet.
* ANSI is a registered trademark of American National Standards Institute, Inc.
6
Transition from error state to no error state.
While in the error state, a subsequent error occurs.
(continued)
*
T1.105 which states only that RDI-L must be gen-
Agere Systems Inc.
May 2001