Simulation and Verification

[pvlitas]

OK, so no Modelsim anymore, I can understand business issues. But I have issues with ISIM and I don't know how to tackle them. I generate waveform numbers in FPGA (for example - DDS). I understand I cannot display bus output in analog form in ISIM - not good, but I would overcome this deficiency if I could get text file with the bus values over time. I could just import it to excel and plot my waveform. Question is - how do I tell it that I want the text file output of particular signal? In Modelsim I could just open list window and dump simulation result there. For the life of me, I cannot find way to do it in ISIM. Anybody can help?

Thanks!

[bassman59]

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pvlitas wrote:

OK, so no Modelsim anymore, I can understand business issues. But I have issues with ISIM and I don't know how to tackle them. I generate waveform numbers in FPGA (for example - DDS). I understand I cannot display bus output in analog form in ISIM - not good, but I would overcome this deficiency if I could get text file with the bus values over time. I could just import it to excel and plot my waveform. Question is - how do I tell it that I want the text file output of particular signal? In Modelsim I could just open list window and dump simulation result there. For the life of me, I cannot find way to do it in ISIM. Anybody can help?

Thanks!

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Read your favorite VHDL text's chapter on the textio package.

[pvlitas]

Unfortunately, considering that dozens of testbench files need to be modified, your suggestion is not economically viable for me, the ptoject budget did not account for this effort. I do have better solution - I go back to ISE 12.2 and Modelsim. Takes no more than 30 seconds and I am back in business. This is not my first, but probably not my last frustration with Xilinx software tools. Why would they drop one tool without having adequate replacement, with practically no advance notice, is beyond me. Somebody at Xilinx need to understand that no matter how superior their silicon devices are, without proper tools they are not that attractive. 

[bassman59]

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pvlitas wrote:

Unfortunately, considering that dozens of testbench files need to be modified, your suggestion is not economically viable for me, the ptoject budget did not account for this effort. I do have better solution - I go back to ISE 12.2 and Modelsim. Takes no more than 30 seconds and I am back in business. This is not my first, but probably not my last frustration with Xilinx software tools. Why would they drop one tool without having adequate replacement, with practically no advance notice, is beyond me. Somebody at Xilinx need to understand that no matter how superior their silicon devices are, without proper tools they are not that attractive. 

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Is it more economically viable to modify all of the testbenches, or to spend the money on a non-toy VHDL simulation tool?

[pvlitas]

I don't know, but I already have the tool...:-)

[duthv]

Hi,

We did a PDN for MXE atleast 4 months in advance of the final purchase date and so we believe it was adequate notification. In 12.2 we added a warning in the tools that MXE was going to go away in the future and to plan for it. While you are correct that there is no support for the Analog Waveform viewer, in ISim, this is on our roadmap as a very high item and we hope to get it into our 14.1 release of ISE. There are some technical limitiations in the GUI interface we use that prevents us from being able to support this any sooner.

Also as part of the PDN, we provided a solution where you can talk to your Mentor sales team to dicuss other options in case ISim is not a viable replacement for MXE. 

http://www.xilinx.com/support/documentation/customer_notices/xcn10028.pdf

If you follow the link and go to www.model.com, there is a pointer there on what options you have if you are coming from the MXE product line.

Also with regards to text output, cant you use a VCD output in order to achieve what you want with getting an ASCII text output file?

Thanks

Duth

[pvlitas]

From your PDN it is not clear that iSim has different set of features, I was thinking it is equivalent to MXE.

I understand the limitation of GUI, this is why I actually prefer the ASCII files. I think feature of dumping to ASCII file is not difficult to implement, this has nothing to do with GUI. Same with simple things like moving cursor to next rising edge or falling edge of waveform, not just next transition. I didn't use VCD files before, I will give it a try.

Thanks,

Igor 

[duthv]

Hi,

This information is too detailed for a PDN and that is why it is not mentioned there. That said if you talk to your local Field AE, he can provide you information on a high-level comparison between the two products. We have to be very careful of the comparison as MXE is based on ModelSim PE, and so we have to be very careful with what comparison we do.

That said VCD is an ASCII file, and you should be able to leverage this for what you need, although try it out..

There is a way in ISim, to move from any rising or falling edge of any signal simialr to any other tools out there. More information on this is covered in the ISim User Guide.

Thanks

Duth

[duthv]

Hi,

Also forgot to mention that in the ISim User Guide, there is a migration guide for MXE users, that tries to ease this hurdle.

Thanks

Duth

[sesilver@gmail.com]

I am also interested in dumping the output of ISIM to a text file. 

Some one mentioned something about a VCD file. Could you please explain how to use this.

I found this but I am not sure how to implement this or if it is what I need.