LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Not fixed size array error in fpga design

I'm doing an fpga design so all arrays have to be fixed. I have an In Range and Coerce function with the three inputs all fixed (according to Context Help when I hover the cursor above the wires). But the outputs, for some reason, don't seem to be fixed. So two questions.
 
1. Why does the In Range and Coerce function change my fixed arrays to not fixed?
2. How do I fix this problem?
 
Thanks.
 
Chuck
0 Kudos
Message 1 of 4
(3,823 Views)

Hello Chuck,

This does seem to be a problem in the LV FPGA diagram and implementation of the In Range function. LV R&D is aware of this issue and will address it.

In the short term the easiest solution is to put a For loop around the In Range function and process each element individually.

A second solution which runs a bit faster than the For Loop is to use a Single Cycle Timed Loop, but it will require a little more logic to handle the Stop condition and Fixed Size array.

I have shown each of these solutions in the attached image.

 

authored by
Christian L, CLA
Systems Engineering Manager - Automotive and Transportation
NI - Austin, TX


  
0 Kudos
Message 2 of 4
(3,806 Views)

Thanks Christian,

I thought I was just being dumb. I'll try your solutions until NI comes out with a fix.

Chuck

0 Kudos
Message 3 of 4
(3,799 Views)

The only primitives in LabVIEW FPGA that support arrays and clusters for polymorphic generation are unary and binary operators (1 or 2 input, 1 output). The fact that this is caught at edit time instead of at code generation time is a benefit 🙂  We will consider this a feature request (not a bug) to be able to support other operations with n inputs.

Regards,

Joseph D.

National Instruments

0 Kudos
Message 4 of 4
(3,620 Views)