DS785UM1
9-25
Copyright 2007 Cirrus Logic
1/10/100 Mbps Ethernet LAN Controller
EP93xx User’s Guide
9
9
9
9.2.3.6 Receive Frame Pre-Processing
The MAC pre-processes all incoming receive frames. First the frame is either passed on to
the next level or discarded according to the destination address filter. The next decision is
whether to accept the frame. A frame is accepted when the frame data are brought into MAC
through internal memory. The final step in frame pre-processing is the decision on causing an
interrupt. These pre-processing steps are detailed in
.
Figure 9-12. Receive Frame Pre-processing
In c o m i n g F r a m e
D e s t i n a t i o n
A d d r e s s
F i l t e r
P r o m i s c u o u s A
IA H a s h A
M u l t i c a s t A
In d i v i d u a l A
B r o a d c a s t A
F i l t e r T a p s :
If t h e f i l t e r i s n o t p a s s e d ,
t h e f r a m e i s d i s c a r d e d .
F i l t e r P a s s e d
A c c e p t ( A )
M a s k
C R C R u n t A
R u n t A
A c c e p t M a s k s :
A c c e p t M a s k
N O T
P A S S E D
A c c e p t M a s k
P A S S E D
S t a t u s i n R x E v e n t
a n d t h e F r a m e B o d y
i s A c c e p t e d i n t o t h e c h i p
i E
M a s k
i E - M a s k T a p s :
In t e r r u p t i f M a s k O K
f r a m e
d i s c a r d e d
F r a m e i s p a s s e d
t o h o s t m e m o r y
b y d e s c r i p t o r
p r o c e s s o r
R e c e i v e S t Q i E
E n d O f S r e a m i E
Summary of Contents for EP93 Series
Page 28: ...P 6 DS785UM1 Copyright 2007 Cirrus Logic Preface EP93xx User s Guide PP P ...
Page 162: ...5 36 DS785UM1 Copyright 2007 Cirrus Logic System Controller EP93xx User s Guide 55 5 ...
Page 576: ...15 18 DS785UM1 Copyright 2007 Cirrus Logic UART2 EP93xx User s Guide 1515 15 ...
Page 634: ...17 38 DS785UM1 Copyright 2007 Cirrus Logic IrDA EP93xx User s Guide 1717 17 ...
Page 648: ...19 6 DS785UM1 Copyright 2007 Cirrus Logic Watchdog Timer EP93xx User s Guide 1919 19 ...
Page 688: ...21 32 DS785UM1 Copyright 2007 Cirrus Logic I2S Controller EP93xx User s Guide 2121 21 ...
Page 790: ...27 20 DS785UM1 Copyright 2007 Cirrus Logic IDE Interface EP93xx User s Guide 2727 27 ...
Page 808: ...28 18 DS785UM1 Copyright 2007 Cirrus Logic GPIO Interface EP93xx User s Guide 2828 28 ...