Hello, I am using ISE Foundation 5.2i with a Spartan2 and am running into the following problems:
- I would like to utilize input/output pads to denote the FPGA I/Os. I typically have been using Schematic Entry and then specify the corresponding pins for the I/O Markers in "Assign Package Pins" (or similar).
- For this design, I would like to use a 32 bit input bus and 32 bits of output. Rather than placing all 32 on my toplevel schematic, it would be cleaner to use a macro to represent a 32 bit Input pad. However, each time I create said macro with 32 I/O Markers going to a bus, it results in a macro block with 32 input leads (one for each marker). Is there a way to create a macro such that the leads only show on the macro level schematic and the toplevel schematic just has the macro form with desired bus32 output designator?
- Is an IPAD (IOPAD,OPAD) of any benefit here? I see them mentioned in the ISE5.2i Libraries Guide (IPAD-primitive,IPAD8-macro) but they do not show up as a selectable part in "Select Part-> I/O' of the Schematic utility. Why?
- Can PACE (Pinout and Constraints Editor) be used to achieve this by creating a UCF for the lowlevel macro? Or is FPGA Editor-> "Add Macro External Pin" better?
Thank you for any help you can provide. Durward