Answers Database
Virtex Readback/ XAPP138: New equation for calculating readback bit positions
Record #7803
Product Family: Hardware
Product Line: Virtex
Product Part: Virtex General Hardware
Problem Title:
Virtex Readback/ XAPP138: New equation for calculating readback bit positions
Problem Description:
Urgency: Standard
General Description: The equation given on page 23 of XAPP138 is incorrect for calculating
the bit position in the readback data, given the .ll file.
Solution 1:
The correct equation is as follows:
Readback Bit Number = Frame Number * Frame Length + Bitmap Length - Frame Offset + 32
The Frame Number and Frame Offset are given in the .ll file
The Frame Length is given : (Xilinx XAPP138, page 11)
The Bitmap Length is different for each Virtex device:
V50 - 234
V100 - 396
V150 - 468
V200 - 540
V300 - 612
V400 - 756
V600 - 900
V800 - 1044
V1000 - 1188
End of Record #7803 - Last Modified: 10/08/99 15:22 |
