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
R
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
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
Reserved