Ethernet Subsystem Registers
14.5.2.44 RX2_FREEBUFFER Register (offset = E8h) [reset = 0h]
RX2_FREEBUFFER is shown in
and described in
CPDMA_INT RECEIVE FREE BUFFER REGISTER CHANNEL 2
Figure 14-72. RX2_FREEBUFFER Register
31
30
29
28
27
26
25
24
Reserved
R-0h
23
22
21
20
19
18
17
16
Reserved
R-0h
15
14
13
12
11
10
9
8
RX_FREEBUFFER
W-0h
7
6
5
4
3
2
1
0
RX_FREEBUFFER
W-0h
LEGEND: R/W = Read/Write; R = Read only; W1toCl = Write 1 to clear bit; -n = value after reset
Table 14-83. RX2_FREEBUFFER Register Field Descriptions
Bit
Field
Type
Reset
Description
31-16
Reserved
R
0h
15-0
RX_FREEBUFFER
W
0h
Rx Free Buffer Count - This field contains the count of free buffers
available.
The rx_pendthresh value is compared with this field to determine if
the receive threshold pending interrupt should be asseted (if
enabled).
This is a write to increment field.
This field rolls over to zero on overflow.
If receive threshold pending interrupts are used, the host must
initialize this field to the number of available buffers (one register per
channel).
The port decrements (by the number of buffers in the received
frame) the associated channel register for each received frame.
This is a write to increment field.
The host must write this field with the number of buffers that have
been freed due to host processing.
1303
SPRUH73H – October 2011 – Revised April 2013
Ethernet Subsystem
Copyright © 2011–2013, Texas Instruments Incorporated