Nortel DMS-100 Series Maintenance Manual page 141

Terminal status table
The terminal status table (TST) has an entry for each line appearance the ESA
software in the RCP can handle. Each entry has two bytes and each byte
contains a data structure. The two data structures are
• Unprotected line data - Unprotected line data helps the ESA CC decide
what action to take when an event message arrives from a terminal. An
event message establishes or changes a line state. The unprotected line
data also keeps track of errors a line generates during call processing.
• ESA call process block (CPB) - The ESA call process block stores the
number times a line tries to re-originate. After the completion of an
origination, the TST stores the index of the call in a call process block.
Every line can have several call processing line states. The call processing line
states determine what the system does with a related message. The ESA CC
first screens the line states of the messages. The call process controller handles
the lines in the idle, originate, abandon, or lockout states. The call process
controller also handles the lines in the call processing busy state. These lines
are processed based on the call processing state in the call processing blocks
of each line. The call process controller ignores the lines in the system busy
(SysB) or manual busy (ManB) states.
Refer to the following figure for a diagram of the TST.
Figure 5-3 Terminal status table
Line
5
7 6
0 Error count/cause
1151 Error count/cause
The first byte (unprotected line data) in the terminal status table includes the
following:
• Error count/cause - The first four bits contain the count of the errors that
line software detects. Each error increases the count. If the error count
Byte 1
4 2 1
3 0
Line state
Line state
DMS-100 Family NA100 Star Remote System XPM15 and up
ESA maintenance overview 5-5
Byte 0
5 4
7 6 3
Call processing block
index/origination count
Call processing block
index/origination count
2 1
0