XRT86VL34 datasheet(38/156 Pages) EXAR

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XRT86VL34

QUAD T1/E1/J1 FRAMER/LIU COMBO - T1 REGISTER DESCRIPTION

REV. V1.2.0

TABLE 18: RECEIVE DATA LINK BYTE COUNT REGISTER (RDLBCR1)

HEX ADDRESS: 0Xn115

BIT

FUNCTION

TYPE

DEFAULT

DESCRIPTION-OPERATION

RBUFPTR

R/W

Receive HDLC1 Buffer-Pointer

This bit Identifies which Receive HDLC1 buffer contains the most

recently received HDLC1 message.

0 - Indicates that Receive HDLC1 Buffer # 0 contains the contents of

the most recently received HDLC message.

1 - Indicates that Receive HDLC1 Buffer # 1 contains the contents of

the most recently received HDLC message.

6-0

RDLBC[6:0]

R/W

0000000

Receive HDLC Message - byte count

The exact function of these bits depends on whether the Receive

HDLC Controller Block #1 is configured to receive MOS or BOS

messages.

In BOS Mode:

These seven bits contain the number of repetitions the BOS mes-

sage must be received before the Receive HDLC1 controller gener-

ates the Receive End of Transfer (RxEOT) interrupt. If these bits are

set to “0000000”, the message will be received indefinitely and no

Receive End of Transfer (RxEOT) interrupt will be generated.

In MOS Mode:

These seven bits contain the size in bytes of the HDLC1 message

that has been received and written into the Receive HDLC buffer.

The length of MOS message shown in these bits include header

bytes such as the SAPI, TEI, Control field, AND the FCS bytes.

XRT86VL34 Datasheet(PDF) 38 Page - Exar Corporation