| Element | XC3000 | XC4000E | XC4000X | XC5200 | XC9000 | Spartan | SpartanXL | Virtex |
|---|---|---|---|---|---|---|---|---|
| IOPAD | Primitive | Primitive | Primitive | Primitive | Primitive | Primitive | Primitive | Primitive |
| IOPD4, IOPAD8, IOPAD16 | Macro | Macro | Macro | Macro | Macro | Macro | Macro | Macro |
IOPAD, IOPAD4, IOPAD8, and IOPAD16 are single and multiple input/output pads. The IOPAD is a connection point from a device pin, used as a bidirectional signal, to a PLD device. The IOPAD is connected internally to an input/output block (IOB), which is configured by the software as a bidirectional block. Bidirectional blocks can consist of any combinations of a 3-state output buffer (such as OBUFT or OFDE) and any available input buffer (such as IBUF or IFD). Refer to the appropriate CAE tool interface user guide for details on assigning pin location and identification.
The LOC attribute cannot be used on IOPAD multiples.
Figure 6.48 IOPAD8 Implementation XC3000, XC4000, XC5200, XC9000, Spartans, Virtex |  |
