| XC3000 | XC4000E | XC4000X | XC5200 | XC9000 | Spartan | SpartanXL | Virtex |
|---|---|---|---|---|---|---|---|
| N/A | Macro | Macro | N/A | N/A | Macro | Macro | Macro |
ILDI_1 is a transparent data latch, which can hold transient data entering a chip. When the gate input (G) is Low, data on the data input (D) appears on the data output (Q). Data on D during the Low-to-High G transition is stored in the latch.
The latch is asynchronously preset, output High, when power is applied. FPGAs simulate power-on when global set/reset (GSR) is active. GSR (XC4000, Spartans) default to active-High but can be inverted by adding an inverter in front of the GSR input of the STARTUP symbol.
For information on legal IFDI, IFDI_1, ILDI, and ILDI_1 combinations, refer to the “ILDI” section.
| Inputs | Outputs | |
|---|---|---|
| G | D | Q |
| 0 | 1 | 1 |
| 0 | 0 | 0 |
| 1 | X | d |
| d = state of input one setup time prior to High-to-Low gate transition | ||
Figure 6.33 ILDI_1 Implementation XC4000, Spartans |  |
Figure 6.34 ILDI_1 Implementation Virtex | |
