XRT86VL38
PRELIMINARY
xr
OCTAL T1/E1/J1 FRAMER/LIU COMBO
REV. P1.0.6
199
T
ABLE
103: LAPD B
UFFER
0 C
ONTROL
R
EGISTER
R
EGISTER
315-410 LAPD B
UFFER
0 C
ONTROL
R
EGISTER
(LAPDBCR0) H
EX
A
DDRESS
: 0
X
n600
TO
0
XN
660
B
IT
F
UNCTION
T
YPE
D
EFAULT
D
ESCRIPTION
-O
PERATION
7-0
LAPD Buffer 0
R/W
0
LAPD Buffer 0 (96-Bytes)
This register is used to transmit and receive LAPD messages within
buffer 0 of the HDLC controller. Any one of the HDLC controller can
be is chosen in the LAPD Select Register (0xn11B). Users should
determine the next available buffer by reading the BUFAVAL bit (bit
7 of the Transmit Data Link Byte Count Register 1 (address 0xn114),
Register 2 (0xn144) and Register 3 (0xn154) depending on which
HDLC controller is selected. If buffer 0 is available, writing to buffer 0
will insert the message into the outgoing LAPD frame after the
LAPD message is sent and the data from the transmit buffer cannot
be retrieved.
After detecting the Receive end of transfer interrupt (RxEOT), users
should read the RBUFPTR bit (bit 7 of the Receive Data Link Byte
Count Register 1 (address 0xn115), Register 2 (0xn145), or Regis-
ter 3 (0xn155) depending on which HDLC controller is selected) to
determine which buffer contains the received LAPD message ready
to be read. If RBUFPTR bit indicates that buffer 0 is available to be
read, reading buffer 0 (Register 0xn600) continuously will retrieve
the entire received LAPD message.
N
OTE
: When writing to or reading from Buffer 0, the register is auto-
matically incremented such that the entire 96 Byte LAPD message
can be written into or read from buffer 0 (Register 0xn600) continu-
ously.
T
ABLE
104: LAPD B
UFFER
1 C
ONTROL
R
EGISTER
R
EGISTER
411-506 LAPD B
UFFER
0 C
ONTROL
R
EGISTER
(LAPDBCR1) H
EX
A
DDRESS
: 0
X
n700
TO
0
XN
760
B
IT
F
UNCTION
T
YPE
D
EFAULT
D
ESCRIPTION
-O
PERATION
7-0
LAPD Buffer 1
R/W
0
LAPD Buffer 1 (96-Bytes)
This register is used to transmit and receive LAPD messages within
buffer 1 of the HDLC controller. Any one of the HDLC controller can
be is chosen in the LAPD Select Register (0xn11B). Users should
determine the next available buffer by reading the BUFAVAL bit (bit
7 of the Transmit Data Link Byte Count Register 1 (address 0xn114),
Register 2 (0xn144) and Register 3 (0xn154) depending on which
HDLC controller is selected. If buffer 1 is available, writing to buffer 1
will insert the message into the outgoing LAPD frame after the
LAPD message is sent and the data from the transmit buffer 1 can-
not be retrieved.
After detecting the Receive end of transfer interrupt (RxEOT), users
should read the RBUFPTR bit (bit 7 of the Receive Data Link Byte
Count Register 1 (address 0xn115), Register 2 (0xn145), or Regis-
ter 3 (0xn155) depending on which HDLC controller is selected) to
determine which buffer contains the received LAPD message ready
to be read. If RBUFPTR bit indicates that buffer 1 is available to be
read, reading buffer 1 (Register 0xn700) continuously will retrieve
the entire received LAPD message.
N
OTE
: When writing to or reading from Buffer 0, the register is auto-
matically incremented such that the entire 96 Byte LAPD message
can be written into or read from buffer 0 (Register 0xn600) continu-
ously.