EmbDev.net

Forum: FPGA, VHDL & Verilog problem with sinulation in ISE (FPGA)


von Zakariya A. (Company: ACT) (zakariy)


Attached files:

Rate this post
useful
not useful
hi there


I got a problem with simulation ........ I am doing a simulation for PN 
code generator and I wrote the sketch for it

I will go for small explanation to make the problem clear


PN generator:
This component implements 7-bit PN code generator using three stages 
Linear Feedback
Shift Register (LFSR).

The Two separate PN generator entities were implemented, one each for 
two sources. The 3-bit initializer (seed) was set within the VHDL coding 
itself in each entity. The PN generator for Source 1 is initialized with 
(S2 S1 S0) = 111 and generates PN code 1110100 whereas the PN generator 
for Source 2 is initialized with (S2 S1 S0) = 110 and generates PN 
code1101001.

so I wrote the sketch

I create two inputs one is( CLOCK ) and the other is (INIT) and the 
output is (PNCODE)


after that I enter the simulation windows

for CLOCK input I right click than select ( Force Clock ) than I give 1 
for ( Leading edge value ) and 0 for Trailing edge value and 100 ns for 
(period)

for INIT input I right click than select  ( Force Constant ) than I give 
0 for ( Force to value )


the problem is the output (PNCODE) is still Undefined and it give no 
thing even after running the simulation


please help ...... I attach the files and sketchs



if the problem not clear yet let me know

von fpgakuechle (Guest)


Rate this post
useful
not useful
Thats not the way to start a simulation. Do not use force clock or force 
sognal during simulation. Instead write a testbench which generates a 
clock and a reset pulse. For example : 
http://vhdlguru.blogspot.de/2010/09/example-4-bit-ring-counter-with.html

Best regards,

von Zakariya A. (Company: ACT) (zakariy)


Rate this post
useful
not useful
fpgakuechle wrote:
> Thats not the way to start a simulation. Do not use force clock or force
> sognal during simulation. Instead write a testbench which generates a
> clock and a reset pulse. For example :
> http://vhdlguru.blogspot.de/2010/09/example-4-bit-ring-counter-with.html
>
> Best regards,

................................................................

oh really.... sorry I am still beginner :)

I will check it

I wrote this topic many where but non answer me

thanks a lot fpgakuechle

Please log in before posting. Registration is free and takes only a minute.
Existing account
Do you have a Google/GoogleMail account? No registration required!
Log in with Google account
No account? Register here.