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
Observer ru551n
Observer
5,993 Views
Registered: ‎02-09-2010

Changing valid frequency range of custom memory part

Jump to solution

Hello!


I am working on a project where we need to create a custom memory part with a desired operating frequency.

 

Therefore I base  my design on a part with similiar row, bank, column structure.

What I need is to changing the valid frequency range of the part, because when I go inte MIG it says that the frequency I select is not valid for the my custom part.

 

Therefore, my question is, how do I change the valid frequency range? Or are there another workaround for this problem?

I've tried altering the .xml files, but that only causes MIG to crash.

 

Sincerely

Sebastian

 

0 Kudos
1 Solution

Accepted Solutions
Xilinx Employee
Xilinx Employee
7,204 Views
Registered: ‎10-23-2007

Re: Changing valid frequency range of custom memory part

Jump to solution

Take a look at the Elpida EDE5116AXXX-8E which looks pretty close to your desired part.  I'm looking at MIG 3.3 which is in ISE 11.4.

 

No, it is not possible to change the frequency via the customization of a part.  Generally the customization is just for tweaking the values a bit - add or subtract a row or column or slightly modify timing for a specific part.

 

Row/bank/column is used by MIG to set the controller options appropriately such as for refresh.  The values must be correct.

View solution in original post

0 Kudos
5 Replies
Xilinx Employee
Xilinx Employee
5,980 Views
Registered: ‎10-23-2007

Re: Changing valid frequency range of custom memory part

Jump to solution
MIG will limit you to frequencies supported by the interface design.  What specific memory part are you trying to use and what interface type is this?  What FPGA family and speed grade are you using?
0 Kudos
Observer ru551n
Observer
5,977 Views
Registered: ‎02-09-2010

Re: Changing valid frequency range of custom memory part

Jump to solution

It's a DDR2 memory part.

It seems that if I choose a certain part as the base part, the custom part gets the same frequency range.

 

We're using a Spartan 6 with speed grade -2, but will probably be upgrading to a -3 in the near future.

 

As for the part number, I can't remember it right now as I'm not at work at the moment. All I can remember at the moment is that it is a 32 x 16 device.

 

 

0 Kudos
Xilinx Employee
Xilinx Employee
5,971 Views
Registered: ‎10-23-2007

Re: Changing valid frequency range of custom memory part

Jump to solution
Yes, I believe you are correct that the base memory frequency is taken from the part you choose to customize.  Is that an issue for you?  Can you find a part with the correct frequency and then customize it for your needs?
0 Kudos
Observer ru551n
Observer
5,947 Views
Registered: ‎02-09-2010

Re: Changing valid frequency range of custom memory part

Jump to solution

As I don't know the inner workings of MIG 3.0, I don't know if it would be possible to choose a part with different row/bank/column configurations, and then changing the address lengths to suit my needs..

If that is possible, I can choose a part with a higher frequency  and then fit the address lengths to the correct configuration.

 

However, we need to be asserted that this works. Preferably from someone with knowledge of how MIG generates custom parts. It wouldn't be very desirable to only have it working in only a test case and nothing else because some parameter is wrong.

 

The memory part which we are using is

 

Micron MT47H32M16HR-25E

 

The part which has the same row/bank/column configuration is:

MT47H32M16XX-37E

 

So my main questions are:

- Does the row/bank/column configuration matter or is it simply reconfigured with the address lengths in MIG?

- Is it somehow possible to reconfigure the valid frequency range  of a custom part?

0 Kudos
Xilinx Employee
Xilinx Employee
7,205 Views
Registered: ‎10-23-2007

Re: Changing valid frequency range of custom memory part

Jump to solution

Take a look at the Elpida EDE5116AXXX-8E which looks pretty close to your desired part.  I'm looking at MIG 3.3 which is in ISE 11.4.

 

No, it is not possible to change the frequency via the customization of a part.  Generally the customization is just for tweaking the values a bit - add or subtract a row or column or slightly modify timing for a specific part.

 

Row/bank/column is used by MIG to set the controller options appropriately such as for refresh.  The values must be correct.

View solution in original post

0 Kudos