The MIG Example Design targeting the KC705 contains new window margining features included starting with the 14.3/2012.3 software release. The window margining can be used to determine if sufficient margin is available for reliable operation and should be used for debugging purposes if data errors are seen after calibration.
The window margining can be performed using a manual or automated flow as described in the
7 Series Hardware Debug Guide available in
(Xilinx Answer 43879). The KC705 MIG Design files contain modifications that enhance the automated window margining feature in the following way:
- Stores left and right edge values from block RAM into registers
- Stores the worst case values in picoseconds
- Calculates margin for each byte group and displays results in picoseconds in ChipScope analyzer
- Scanning of the I/O margin continues running indefinitely until a reset or a value of 0 on the VIO Activate_reg_output port occurs. See image below:

AR52808.png