Answers Database

XBLOX 5.x and View/PROsim: Finding and assigning values to XBLOX I/O (INPUTS, OUTPUTS, and BIDIR_IO)


Record #541

Product Family:  Software

Product Line:  FPGA Core

Problem Title:
XBLOX 5.x and View/PROsim: Finding and assigning values to XBLOX I/O
(INPUTS, OUTPUTS, and BIDIR_IO)



Problem Description:
How do I simulate XBLOX INPUTS, OUTPUTS, and BIDIR_IO symbols?	I often get
"cannot find node or vector" errors in View/PROsim.

For a functional or timing simulation, where it may be necessary to assign
a value to such I/O pads, it is not always easy to figure out how the
associated signals have been renamed.


Solution 1:

Be precise: predefine the whole symbol name.

1. Select the XBLOX I/O symbol (INPUTS, OUTPUTS, or BIDIR_IO).

2. Attach a label on it (in this example, label=IN).

3. Define a PADNAME attribute (attribute PADNAME=DATA).

WARNING!  Do NOT label the X-BLOX component with the same name as the
PADNAME attribute applied to it. X-BLOX currently cannot handle this case
correctly, creating incorrect connectivity.  Also, do NOT use a PADNAME of
INPUTS or OUTPUTS, as this may short together the ends of each I/O buffer!

4. Simulate.

From a View/PROsim window or a command file (.cmd):

   vector datain in\data[3:0]
   assign datain 1110
   sim 1000

If the bus is wider, you can change the radix with:

   vector datain in\data[15:0]
   radix hex datain
   assign datain FF02
   sim 1000



End of Record #541