SMC Networks PL241 Timing diagrams, Signals, Signal level, Lower-case n, Prefix AR, Prefix AW

Models: AHB SRAM/NOR PL241

1 110
Download 110 pages 44.4 Kb
Page 12
Image 12
Timing diagrams

Preface

Note

Angle brackets can also enclose a permitted range of values. The example, <0-3>, shows that in name extensions, only one of the values 0, 1, 2, or 3 is valid.

Timing diagrams

The figure named Key to timing diagram conventions explains the components used in timing diagrams. Variations, when they occur, have clear labels. You must not assume any timing information that is not explicit in the diagrams.

Shaded bus and signal areas are undefined, so the bus or signal can assume any value within the shaded area at that time. The actual level is unimportant and does not affect normal operation.

&ORFN

+,*+WR/2:

7UDQVLHQW Signals +,*+/2:WR+,*+ Signal level

%XVVWDEOH %XVWRKLJKLPSHGDQFH Lower-case n

%XVFKDQJH Prefix A

+LJKLPSHGDQFHWRVWDEOHEXV Denotes global Advanced eXtensible Interface (AXI) signals.

Key to timing diagram conventions

Signals

The signal conventions are:

Signal level

The level of an asserted signal depends on whether the signal is

 

active-HIGH or active-LOW. Asserted means HIGH for

 

active-HIGH signals and LOW for active-LOW signals.

Lower-case n

Denotes an active-LOW signal.

Prefix A

Denotes global Advanced eXtensible Interface (AXI) signals.

Prefix AR

Denotes AXI read address channel signals.

Prefix AW

Denotes AXI write address channel signals.

xii

Copyright © 2006 ARM Limited. All rights reserved.

ARM DDI 0389B

Page 12
Image 12
SMC Networks PL241, AHB SRAM/NOR manual Timing diagrams, Signals, Signal level, Lower-case n, Prefix AR, Prefix AW