XRT86SH328_07 Datasheet, PDF (284/339 Pages) Exar Corporation – 28-CHANNEL DS1/E1 FRAMER/LIU WITH DS3 MUX & VT-MAPPER - SONET

XRT86SH328
PRELIMINARY
28-CHANNEL DS1/E1 FRAMER/LIU WITH DS3 MUX & VT-MAPPER - SONET APPLICATIONS REV. P1.0.6
the remote terminal.
` 0 = Disabled
` 1 = Transmit the abort sequence
BIT 2 - Transmit Idle (Flag Sequence Byte):
This bit configures the transmit HDLC controller to unconditionally transmit a repeating string of flag sequence octets
(0x7E) in the data link channel to the remote terminal. In normal conditions, the transmit HDLC controller will repeatedly
transmit the flag sequence octet whenever there is no MOS message to transmit to the remote terminal equipment.
However, if the user invokes this transmit idle sequence feature, then the transmit HDLC controller will
UNCONDITIONALLY transmit a repeating stream of the flag sequence octet (thereby overwriting all outbound MOS
data link messages).
` 0 = Disabled
` 1 = Transmit a repeating string of Flag Sequence Octets (0x7E)
NOTE: This bit is ignored if the transmit HDLC controller is operating in the BOS mode (bit 0 within this register is set to
0).
BIT 1 - Transmit Frame Check Sequence Enable:
This bit is used to configure the transmit HDLC controller to compute and append FCS octets to the back end of each
outbound MOS data link message.
` 0 = Disabled
` 1 = Compute and append the FCS octets to the back end of each outbound MOS data link message
NOTE: This bit is ignored if the transmit HDLC controller ahs been configured to operate in the BOS mode - BIT 0
within this register is set to 0).
BIT 0 - MOS / BOS:
This bit is used to configure transmit and receive the HDLC to be transmitting and receiving either BOS (bit oriented
signaling) or MOS (message oriented signaling) frames.
` 0 = Transmit and Receive BOS Messages
` 1 = Transmit and Receive MOS Messages
TABLE 408: T1 FRAMER BLOCK - TRANSMIT DATA LINK CONTROL REGISTER (ADDRESS = 0XN114, WHERE N
RANGES IN VALUE FROM 0X01 TO 0X38)
BIT7
BIT6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
TxHDLC
BUFAVAIL
Transmit HDLC Message Byte Count
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
0
0
BIT7 - Transmit HDLC Buffer Available:
This bit has different functions depending upon whether the user is writing to or reading from this register.
If User is Writing Data Into This Register Bit
` 0 = Configures the transmit HDLC controller to read out and transmit the data, residing within the transmit HDLC buffer
0 via the data link channel to the remote terminal equipment.
` 1 = Configures the transmit HDLC controller to read out and transmit the data, residing within the transmit HDLC buffer
1 via the data link channel to the remote terminal equipment.
If User is Reading Data From This Register Bit
` 0 = Indicates that transmit buffer 0 is the next available buffer. In this case, to write in the contents of a new outbound
data link message into the transmit HDLC message buffer, the message should be written into buffer 0.
` 1 = Indicates that transmit buffer 1 is the next available buffer. In this case, to write in the contents of a new outbound
data link message into the transmit HDLC message buffer, the message should be written into buffer 1.
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