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AR# 44313

13.3 PlanAhead - [ALGAI 0] Incorrect value '226.000000' specified for property 'REFCLK_FREQUENCY'


When I open up the netlist design in the PlanAhead tool, the following warnings occur:

"[ALGAI 0] Incorrect value '226.000000' specified for property 'REFCLK_FREQUENCY' (file = phy_dqs_iob.v, line = 178)
[ALGAI 0] Incorrect value '226.000000' specified for property 'REFCLK_FREQUENCY' (file = phy_dm_iob.v, line = 447)
[ALGAI 0] Incorrect value '226.000000' specified for property 'REFCLK_FREQUENCY' (file = phy_dq_iob.v, line = 203)"

What is wrong?


The allowed REFCLK_FREQUENCY calculated by the PlanAhead tool was taken from the frequency setting found in the libraries guide for Virtex-6 devices.

This value in the library guide is incorrect,and since the PlanAhead toolwas designed to use those values, it is reporting this out.

For Virtex-6 devices, the IODELAY REFCLK can be 200 or 300 MHz (in HIGH PERFORMANCE mode) with a +/- 10 MHz variation.

constant MAX_REFCLK_FREQUENCYL : real := 210.0;
constant MIN_REFCLK_FREQUENCYL : real := 190.0;

constant MAX_REFCLK_FREQUENCYH : real := 310.0;
constant MIN_REFCLK_FREQUENCYH : real := 290.0;

This issue is fixed in the 13.4 PlanAhead tool.

AR# 44313
Date 05/16/2012
Status Active
Type Known Issues
  • PlanAhead - 13.4