Selecting the Configuration Mode
Each configuration interface corresponds to one or more configuration modes and bus
widths.
- Select the configuration mode by setting the appropriate condition on the
CBUS[2:0],, andinput . - Do not toggle the mode before the enters user mode.
| Configuration Mode | Parallel/Serial | CSI | CBUS2, CBUS1, CBUS0 | Width | ||
|---|---|---|---|---|---|---|
| SPI Active | Serial | 1 | 1 | 1 | x1 | |
| Parallel | 1 | 1 | 1 | x2 | ||
| Parallel | 1 | 1 | 1 | x4 | ||
| SPI Passive | Serial | 1 | 1 | 0 | x1 | |
| Parallel | 1 | 1 | 0 | x2 | ||
| Parallel | 1 | 1 | 0 | x4 | ||
| Parallel | 1 | 1 | 0 | x8 | ||
| Parallel | 1 | 1 | 0 | x16 | ||
| Parallel | 1 | 1 | 0 | x32 |
The JTAG/boundary-scan configuration interface is always available regardless of pin settings. If you send configuration instructions to the JTAG interface, the overwrites the previous configuration.
Note: You must set the configuration mode in the
software; the software includes the mode and other configuration options in the
bitstream.