SMC Networks PL241, AHB SRAM/NOR manual SMC Opmode Registers 0-3 at 0x1104, 0x1124, 0x1144

Models: AHB SRAM/NOR PL241

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3.3.10SMC Opmode Registers <0-3> at 0x1104, 0x1124, 0x1144, 0x1164

Programmer’s Model

Table 3-10lists the register bit assignments.

Table 3-10 smc_sram_cycles Register bit assignments

Bits

Name

Function

 

 

 

[31:20]

-

Reserved, read undefined

 

 

 

[19:17]

t_tr

Turnaround time for SRAM chip configuration

 

 

 

[16:14]

t_pc

Page cycle time for SRAM chip configuration

 

 

 

[13:11]

t_wp

smc_we_n assertion delay

 

 

 

[10:8]

t_ceoe

smc_oe_n assertion delay for SRAM chip configurations

 

 

 

[7:4]

t_wc

Write cycle time

 

 

 

[3:0]

t_rc

Read cycle time

 

 

 

3.3.10SMC Opmode Registers <0-3> at 0x1104, 0x1124, 0x1144, 0x1164

There is an instance of the smc_opmode Register for each chip supported. This register is read-only and cannot be read in the Reset state.

The reset values of these registers are configuration-dependent. You can set the memory width for the chip select 0 of each memory interface with a tie off to enable booting from that chip. The reset value of memory width for all other chip selects is the configured width. You must set all other bits to 0x0, apart from address_match and address_mask. These are set by tie-offs at the top level.

Figure 3-15shows the register bit assignments.



 

 

    

  

 



DGGUHVVBPDWFK

DGGUHVVBPDVN

 

ZUBEO

UGBEO

PZ

EXUVWBDOLJQ Manual background

EOV

DGY

EDD

ZUBV\QF

UGBV\QF

Figure 3-15 smc_opmode Register bit assignments

3-16

Copyright © 2006 ARM Limited. All rights reserved.

ARM DDI 0389B

Page 76
Image 76
SMC Networks PL241, AHB SRAM/NOR manual SMC Opmode Registers 0-3 at 0x1104, 0x1124, 0x1144