UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

cancel
Showing results for 
Search instead for 
Did you mean: 
Highlighted
Participant ucabsdp
Participant
5,021 Views
Registered: ‎07-06-2013

Div 5.1 giving incorrect results for signed negative inputs

Hi,

 

I am using Div Gen 5.1 to generate a divider, i have found when an input is -ve and the other +pv it fails to give the correct result.

 

I am using this as part of a hardware design to be presented in a conference and need this issue resolved asap!

 

Thanks 

Sam

 

--I would also like to note, Xilinx software has been a constant battle to use (over the last 2 years!) with numerous bugs.

Tags (3)
0 Kudos
4 Replies
Participant ucabsdp
Participant
5,012 Views
Registered: ‎07-06-2013

Re: Div 5.1 giving incorrect results for signed negative inputs

I am running this in 32 bit as I had too many bug in 64 bit, but would this problem be resolved in 64? I am using vivado 2013.3, is this issue resolved in later versions? I am skeptical to upgrade as I know there will be another whole host of bugs I iwll have to learn to work around!
0 Kudos
Xilinx Employee
Xilinx Employee
4,999 Views
Registered: ‎02-06-2013

Re: Div 5.1 giving incorrect results for signed negative inputs

Hi

 

We don't have any known issue's which you have described.

 

Can you attach a simulation snapshot showing what you are seeing and what you are expecting to look at it and give you further suggestion on this.

 

Regards,

Satish

--------------------------------------------------​--------------------------------------------
Kindly note- Please mark the Answer as "Accept as solution" if information provided is helpful.

Give Kudos to a post which you think is helpful.
--------------------------------------------------​-------------------------------------------
0 Kudos
Participant ucabsdp
Participant
4,991 Views
Registered: ‎07-06-2013

Re: Div 5.1 giving incorrect results for signed negative inputs

Hi,

 

The I have worked out the issue is when the result is 0> x >-1 ,  i.e just negative fractionals quotient = 0, the quoitent part is not signed extended to a negative. 

 

I guess then the question is how can I construct a reliable fixed-point result from the axi-result format Quotient-Frac, in the case that there is no quotient and I need to sign extend myself.

 

 

0 Kudos
Participant ucabsdp
Participant
4,990 Views
Registered: ‎07-06-2013

Re: Div 5.1 giving incorrect results for signed negative inputs

0 Kudos