XRT7245
DS3 UNI FOR ATM
á
PRELIMINARY
REV. 1.03
82
Read in the PMDL Message from the “Transmit
LAPD Message” Buffer.
Encapsulate the PMDL Message into a complete
LAPD Message frame by including the necessary
header and trailer bytes (e.g., flag sequence bytes,
SAPI, CR, EA values, etc.).
Compute the frame check sequence word (16 bit
value)
Insert the Frame Check Sequence value into the 2
octet slot after the payload section of the Message.
Proceed to transmit the LAPD Message Frame to
the “far end” terminal via the outgoing DS3 frames.
Writing a “1” to this bit-field start the transmission of
the LAPD Message Frame, via the LAPD Transmitter.
For more information on the LAPD Transmitter,
please see Section 6.4.3.1.3.
Bit 2—TxDL Busy
This “Read-Only” bit-field allows the local μP to “poll”
and determine if the LAPD Transmitter has completed
its transmission of the LAPD Message frame. This
bit-field will contain a “1”, if the LAPD Transmitter is
still transmitting the LAPD Message frame to the “far-
end” terminal. This bit-field will toggle to “0”, once the
LAPD Transmitter has completed its transmission of
the LAPD Message frame.
For more information on the LAPD Transmitter,
please see Section 6.4.3.1.3.
Bit 1—TxLAPD Interrupt Enable
This “Read/Write” bit-field allows the user to enable
or disable the “LAPD Message Frame Transmission
Complete” interrupt.
Writing a “0” to this bit-field disables this interrupt.
Writing a “1” to this bit-field enables this interrupt.
Bit 0—TxLAPD Interrupt Status
This “Reset Upon Read” bit-field indicates whether or
not the “LAPD Message frame Transmission Complete”
interrupt has occurred since the last read of this reg-
ister. The purpose of this interrupt is to let the local
μP know that the LAPD Transmitter has completed its
transmission of the LAPD Message frame (containing
the latest PMDL message); and is now ready to
transmit another LAPD Message frame.
A “0” in this bit-field indicates that the “LAPD Message
frame Transmission Complete” interrupt has not
occurred since the read of this register. A “1” in this
bit-field indicates that this interrupt has occurred
since the last read of this register.
For more information on the LAPD Transmitter,
please see Section 6.4.3.1.3.
3.3.2.32
PMON LCV Event Count Register—MSB
This “Reset-upon-Read” register, along with the
“PMON LCV Event Count Register—LSB” (Address
= 21h) contains a 16-bit representation of the number
of “Line Code Violations” that have been detected by
the Receive DS3 Framer, since the last read of these
registers.
This register contains the MSB (or Upper-Byte) value
of this 16 bit expression.
3.3.2.33
PMON LCV Event Count Register—LSB
Address = 20h, PMON LCV Event Count Register—MSB
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
LCV Count—High Byte
RUR
RUR
RUR
RUR
RUR
RUR
RUR
RUR
0
0
0
0
0
0
0
0
Address = 21h, PMON LCV Event Count Register—LSB
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
LCV Count—Low Byte
RUR
RUR
RUR
RUR
RUR
RUR
RUR
RUR
0
0
0
0
0
0
0
0