
XRT84L38
393
REV. 1.0.1
OCTAL T1/E1/J1 FRAMER
shows configuration of the Transmit D or E Channel Source Select [1:0] bits of the Transmit Data Link Select
Register (TSDLSR).
TRANSMIT DATA LINK SELECT REGISTER (TSDLSR) (INDIRECT ADDRESS = 0XN0H, 0X0AH)
For the Transmit HDLC Controller to be input source of D or E channel, the Transmit D or E Channel Source
Select [1:0] bits of the Transmit Data Link Select Register has to be set to 01.
13.1.3
Transmit BOS (Bit Oriented Signaling) Processor
The Transmit BOS Processor handles transmission of BOS messages through the DS1 data link channel. It
determines how many repetitions a certain BOS message will be transmitted. It also inserts BOS IDLE flag
sequence and ABORT sequence to be transmitted on the data link channel. In the later sections, we will
discuss BOS message format and how to transmit BOS message.
13.1.3.1
Description of BOS
Bit-Oriented Signaling message is a sixteen-bit pattern carries the form of:
(0d5d4d3d2d1d0011111111)
Where d5 is the MSB and d0 is the LSB. The rightmost "1" is transmitted first. Bit-Oriented Signaling message
is classified into the following two groups:
Priority Codeword Message
Command and Response Information
Priority Codeword message is preemptive and has the highest priority among all data link information. Priority
Codeword information indicates a condition that is affecting the quality of service and thus shall be transmitted
until the condition no longer exists. The duration of transmission should not be less than one second. Priority
codeword information may be interrupted by software for 100 milliseconds to send maintenance commands
with a minimum interval of one second between interruptions. Yellow alarm (00000000 11111111) is the only
priority message defined in standard.
Command and response information is transmitted to perform various functions. The BOS Processor send
command and response message by transmitting a minimum of 10 repetitions of the appropriate codeword
pattern. Command and response data transmission initiates action at the remote end, while the remote end
will respond by sending Bit-Oriented response message to acknowledge the received commands. The
activation and deactivation of line loop-back and payload loop-back functions are this type of signal.
13.1.3.2
How to configure the BOS Processor Block to transmit BOS
This section describes how to configure the BOS Processor Block to transmit BOS message in a step-by-step
basis.
13.1.3.2.1
Step 1: Find out the next available transmit data link buffer
To transmit a bit-oriented signal, a repeating message is sent of the form (0d5d4d3d2d1d0011111111), where
the "d5d4d3d2d1d0" represents a six-bit message. The user is recommended to read Transmit Data Link Byte
Count Register for next available transmit data link buffer number.
B
IT
N
UMBER
B
IT
N
AME
B
IT
T
YPE
B
IT
D
ESCRIPTION
3-2
Transmit D or E
Channel Source
Select [1:0]
R/W
00 - The data link bits are inserted into the D or E channel through the Transmit
Serial Data input Interface via the TxSer_n pins.
01 - The data link bits are inserted into the D or E channel through the Transmit
HDLC Controller.
10 - The data link bits are inserted into the D or E channel through the Transmit
Serial Data input Interface via the TxSer_n pins.
11 - The data link bits are inserted into the D or E channel through the Transmit
Fractional T1 Input Interface via the TxFrT1_n pins.