SMC Networks PL241, AHB SRAM/NOR manual For tRC

Models: AHB SRAM/NOR PL241

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For tRC:

Functional Overview

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Figure 2-23 Synchronous read and asynchronous write

Programming tRC and tWC when the controller operates in synchronous mode

For tRC:

when using memory devices that are not wait-enabled, you must program tRC to be the number of clock cycles required before valid data is available following the assertion of cs_n

when using memory devices that are wait-enabled, you must program tRC to be the number of clock cycles required before wait is active and stable, following the assertion of cs_n. That is:

t_RC = 3 + t_CEOE

Note

t_CEOE is only required if wait is asserted when oe_n goes LOW.

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Copyright © 2006 ARM Limited. All rights reserved.

ARM DDI 0389B

Page 58
Image 58
SMC Networks PL241, AHB SRAM/NOR manual For tRC