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AR# 35575

12.1 MAP - global_opt can produce ERROR:XST:1652


In ISE software 12.1, the following error can be seen in MAP when the global_opt switch is used:

"ERROR:Xst:1652 - Value can not be computed: either not set or no related TimeSpec"
This appears to be related to invalid TIMESPEC creation within the customer's UCF file. Check the NGDbuild/Translate log file for warnings of the following type:
"WARNING:ConstraintSystem:3 - Constraint < TIMESPEC "TS_MC_RD_DATA_SEL" = FROM "TNM_RD_DATA_SEL" TO FFS "TS_SYS_clk0" * 4; > [Pin_constrain.ucf(268)]: This constraint will be ignored because the relative clock constraint named'TS_SYS_clk0' was not found."


To work around this issue, the customer's UCF file should be enhanced to remove these types of warnings.
Alternatively, you can remove "global_opt" switch from the MAP command.
AR# 35575
Date Created 06/02/2010
Last Updated 12/15/2012
Status Active
Type General Article
  • ISE Design Suite - 12.1
  • ISE Design Suite - 12.2