Rx_a buffer descriptor pointer offset register – Digi NS9750 User Manual

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E t h e r n e t C o m m u n i c a t i o n M o d u l e

RX_A Buffer Descriptor Pointer Offset register

Address: A060 0A28

D07:00

TXERBD

0x00

Contains the pointer (in the TX buffer descriptor RAM) to
the last buffer descriptor of a frame that was not
successfully transmitted. TXERBD is loaded by the

TX_WR

logic when a transmit frame is aborted by the

MAC or when the MAC finds a CRC error in a frame.
TXERBD also is loaded if a buffer descriptor that is not
the first buffer descriptor in a frame does not have its F bit
set.

Note:

This pointer is the 8-bit physical address of the
TX buffer descriptor RAM, and points to the
first location of the four-location buffer
descriptor. The byte offset of this buffer
descriptor can be calculated by multiplying this
value by 4.

Note:

Software uses TXERBD to identify frames that
were not transmitted successfully.

Bits

Access

Mnemonic

Reset

Description

Table 244: TX Error Buffer Descriptor Pointer register

Reserved

RXAOFF

Reserved