On Jul 1, 9:40*am, Sharanbr <sharan.basa...@gmail.com> wrote:
> On Jul 1, 3:05 pm, "Symon" <symon_bre...@hotmail.com> wrote:
>
> >http://www.xilinx.com/itp/xilinx7/bo...gd0140_101.htm...
>
> Thanks, but I was not asking about the setting up the constraints for
> fpga pinouts, it was a larger question.
> How do I ensure that I have got a fairly accurate pinout (assuming
> meeting timing is not an issue) when
> the design is still under development. Do people create dummy FPGA top
> and use special tools that only
> check the validity of the pinouts wrt to the selected device?
>
> Look at it this way - people in S/W world exchange information about
> each other's module
> by providing the class prototypes and this happens much before the
> code has been developed.
>
> Regards,

You should look at the datasheet and user guide for the device you're
using, and understand the functionality of the different types of pins
it has. Then, you can start deciding which pins can go where. Board
layout concerns and I/O standards come into play as well.