Rainbow Electronics W90N740 User Manual
Page 113
W90N740
Publication Release Date: November 26, 2004
- 109 -
Revision A4
DMA Receive Frame Status Register (DMARFS_0, DMARFS_1)
Register Address R/W
Description
Reset
Value
DMARFS_0 0xFFF0.30C8 R/W DMA
Receive Frame Status Register
0x0000.0000
DMARFS_1 0xFFF0.38C8 R/W DMA
Receive Frame Status Register
0x0000.0000
31
30
29
28
27
26
25
24
Reserved
23
22
21
20
19
18
17
16
Reserved
15
14
13
12
11
10
9
8
RXFS
7
6
5
4
3
2
1
0
RXFS
RXFS [15:0]: DMA receive frame length
Default value: 0000h
When an early notification interrupt occurs, the frame length/type field contains the size of the frame
that is currently being received, and stores in RXFS.
To save space in the frame memory buffer, users can determine the current frame length by :
1. Enable the early notification interrupt (set EnDEN bit in MIEN)
2. Read the RXFS field when the interrupt occurs
Note: all the DMARFS bits are cleared by write ones; writing zeros has no effect.