SMC Networks PL241, AHB SRAM/NOR manual Multiplexed-mode page accesses are not supported

Models: AHB SRAM/NOR PL241

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Multiplexed-mode page accesses are not supported.

Functional Overview

Figure 2-18shows a page read access, with an initial access time, tRC, of three cycles, an output enable assertion delay, tCEOE, of two cycles and a page access time, tPC, of one cycle.

Page mode is enabled in the SMC by setting the opmode Register for the relevant chip to asynchronous reads and the burst length to the page size.

Note

Multiplexed-mode page accesses are not supported.

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Figure 2-18 Page read

Synchronous burst read

Table 2-12and Table 2-13list the smc_opmode0_<0-3> and SRAM Register settings.

Table 2-12 Synchronous burst read opmode chip register settings

Field

mw

rd_sync rd_bl

wr_sync

wr_bl

baa

adv

bls

ba

 

 

 

 

 

 

 

 

 

 

 

 

Value

-

b1

<burst length>

-

 

-

-

b1

-

-

 

 

 

 

 

 

Table 2-13 Synchronous burst read SRAM cycles register settings

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Field

t_rc

t_wc

t_ceoe

t_wp

t_pc

t_tr

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Value

b0100

-

b010

 

-

-

-

 

 

 

 

 

 

 

 

 

 

 

 

2-32

Copyright © 2006 ARM Limited. All rights reserved.

ARM DDI 0389B

Page 52
Image 52
SMC Networks PL241, AHB SRAM/NOR manual Multiplexed-mode page accesses are not supported