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AR# 13201

12.1 Speed File - What does the Twos timing parameter/symbol stand for? (Tshcko16, Tshcko32)


Keyword: TWR, Timing Analyzer, TRCE, Tshcko, RAM, report  


Below is a snippet of a timing report (.twr/.twx) file: 

 Timing Report Example
Timing Report Example


What does the "Twos" symbol mean?


The Twos symbol is the same as Tshcko16, Tshcko32, or Treg in the data sheet. See the Virtex-E data sheet: http://www.xilinx.com/support/documentation/virtex-e_data_sheets.htm.

"Tshcko16/32" denotes clock-to-out of Distributed RAM during a WRITE command. "Treg" denotes clock-to-out of a shift register (SRL16). 


The Twos value can vary depending on the output path of the RAM or SRL. 


For example, the delay of the RAM output going directly to the X/Y output pin of the slice is different from the delay of the same RAM going to MUXF5 before being output to the slice's X/Y pin.

AR# 13201
Date Created 08/29/2007
Last Updated 05/14/2014
Status Archive
Type General Article