A special Sync word is used to allow configuration logic to align at a 32-bit word boundary. No packet is processed by the FPGA until the Sync word is found. The bus width must be detected successfully for parallel configuration modes before the Sync word can be detected. The following table shows the Sync word in an unswapped bitstream format.
| 31:24 | 23:16 | 15:8 | 7:0 |
|---|---|---|---|
0xAA
|
0x99
|
0x55
|
0x66
|