User guide

128 www.xilinx.com Spartan-6 FPGA Configuration User Guide
UG380 (v2.7) October 29, 2014
Chapter 6: Readback and Configuration Verification
The drawback to this approach is that in addition to storing the initial configuration
bitstream and the
MSD file, the golden RBD file must be stored somewhere, increasing
the overall storage requirement.
2. Compare readback data to the configuration BIT file, mask using the
MSK file (see
Figure 6-5).
Another approach for verifying readback data is to compare the readback data stream
to the frame data within the FDRI write in the original configuration bitstream,
masking readback bits with the
MSK file.
After sending readback commands to the device, comparison begins by aligning the
beginning of the readback frame data to the beginning of the FDRI write in the BIT
and
MSK files. The comparison ends when the end of the FDRI write is reached.
This approach requires the least in-system storage space, because only the
BIT, MSK,
and readback commands must be stored.
X-Ref Target - Figure 6-4
Figure 6-4: Comparing Readback Data Using the MSD and RBD Files
Pad Frame
Frame Data
Pad Frame
File Header
Frame Data
Mask
To t al
Number of
Device
Frames
1 Frame
Readback
Data Stream
UG380_c6_04_042909
MSD
File
Pad Frame
File Header
Frame Data
RBD
File