描述

The SPI-4.2 Core has certain "static configuration signals" that control various aspects of the core functionality. 

Can these values be changed in-circuit?

解决方案

Users of the core can change the following static settings for the SPI-4.2 Core during reset assertion (but NOT during regular operation, or on the fly): 

NumDip4Errors 

NumTrainSequences 

SnkCalendar_M 

SnkCalendar_Len 

SnkAFThresAssert 

SnkAFThresNegate 

SrcBurstLen 

SrcAFThresAssert 

SrcAFThresNegate 

SrcCalendar_M 

SrcCalendar_Len 

DataMaxT 

AlphaData 

NumDip2Errors 

NumDip2Matches 

The following steps to perform these changes are recommended. These steps have been verified in functional and timing simulations with the SPI-4.2 v9.3 Core, and information has been added to that User Guide. 

1. Disable the sink and source core (SnkEn and SrcEn signals). 

2. Assert core reset (Reset_n = 0). 

3. Change the desired static configuration signals. 

4. Deassert reset (Reset_n=1). 

5. Wait at least 10 clock cycles of RDClkDiv_GP for the sink static configuration signals to settle, and 10 clock cycles of SysClkDiv_GP for the source static configuration signals to settle and propagate to the logic. 

6. Enable the core and wait for the core to achieve synchronization, then continue normal operation. 

Revision History 

06/24/2009 - Initial Release 

09/16/2009 - Updated verification info