User manual

Dealing with a pin conflict
In the lab exercise you were asked to add a line to your .qsf file to avoid
a pin assignment problem. The following is an alternate way to
accomplish the same task.
Pin AD25 of the DE2-70’s FPGA has two uses. One is as a JTAG pin and
the second as an input/output pin. The DE2-70 connects this pin to slide
switch iSW[7].
When a design uses iSW[7] this will lead to a fatal error.
To correct the situation:
Assignments -- Device -- Device and Pin Options
Click on the Value entry for nCEO and select Use as regular I/O. OK
click your way out.
This can be handled in the project .qsf file as well.
EECS 452 – Fall 2014 Lecture 5 – Page 44/143 Tuesday – September 16, 2014