Intel® Quartus® Prime Software
Intel® Quartus® Prime Design Software, Design Entry, Synthesis, Simulation, Verification, Timing Analysis, System Design (Platform Designer, formerly Qsys)
16612 Discussions

Probem in a state machine code

Altera_Forum
Honored Contributor II
1,137 Views

Hi, I'm new in VHDL and I have a problem with this code: 

 

The problem is that when I program it on The FPGA, even when SW(4) is equal to 0, LEDR(0) is equal to 1. And It stays on this state even if I move on the others switches (SW(0),SW(1),SW(2)). 

 

Thank you very much for any help.
0 Kudos
8 Replies
Altera_Forum
Honored Contributor II
387 Views

I didn't look at your code, but you should check your board documentation to see if the switches or LEDs are wired as active low rather than active high.

0 Kudos
Altera_Forum
Honored Contributor II
387 Views

 

--- Quote Start ---  

I didn't look at your code, but you should check your board documentation to see if the switches or LEDs are wired as active low rather than active high. 

--- Quote End ---  

 

I have already done it. They are active high.
0 Kudos
Altera_Forum
Honored Contributor II
387 Views

Have you written a simulation testbench?  

Why have you used > to compare the switch values?
0 Kudos
Altera_Forum
Honored Contributor II
387 Views

 

--- Quote Start ---  

Have you written a simulation testbench?  

Why have you used > to compare the switch values? 

--- Quote End ---  

 

 

No, I didn't write a simulation testbench. I've just tested this code on the FPGA. 

Actually, I didn't write the code. It is automatically generated by HDL coder based on a state machine in Matlab/Simulink. That's why > are used. But, I've tried ='1' to compare the switch values and it leads always to the same results : the code doesn't work. 

Please, any help ?
0 Kudos
Altera_Forum
Honored Contributor II
387 Views

Have you assigned the correct pins to the ports?

0 Kudos
Altera_Forum
Honored Contributor II
387 Views

 

--- Quote Start ---  

Have you assigned the correct pins to the ports? 

--- Quote End ---  

 

Yes, I absolutely did. 

The problem can't be in the syntax of clk_50 ? Shouldn't I write clock_50 rather than clk_50 ?
0 Kudos
Altera_Forum
Honored Contributor II
387 Views

if there was a syntax error, it would be obvious. 

Have you got the clock connected?
0 Kudos
Altera_Forum
Honored Contributor II
387 Views

 

--- Quote Start ---  

if there was a syntax error, it would be obvious. 

Have you got the clock connected? 

--- Quote End ---  

 

Yes, the clock is connected.
0 Kudos
Reply