# Inexplicable behavior of the AXI-Lite VIP in Modelsim **URL:** \ **Category:** Bitvis VIP AXI-Lite\ **Tags:** uvvm, question, axilite\ **Created:** [February 8, 2021, 10:08am UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146 "2021-02-08T10:08:42Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![ktorkelson](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/ktorkelson/32/66_2.png) [@ktorkelson](https://forum.uvvm.org/u/ktorkelson)\ **Post date:** [February 8, 2021, 10:08am UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/1 "2021-02-08T10:08:42Z")
Hi all, I tried to use the latest AXI-Lite VIP in Modelsim (2020.4), but now I’m already stuck when starting the simulator. A short info: I already use the previous VIP and everything has worked flawlessly so far. I wanted to switch to the new version, but now I have the problem that Modelsim stops loading the design with the following error: ```auto # ** Fatal: (SIGSEGV) Bad handle or reference. # Time: 0 ns Iteration: 0 Process: / test_tb / axilite_vvc_1 / read_address_channel_executor File: V:/UVVM /script/../bitvis_vip_axilite/script/../src/axilite_vvc.vhd # FATAL ERROR while loading design ``` In my test bench, which leads to this error, only the AXI-Lite VCC is instantiated, nothing else. If I start the AXI-Lite VCC component itself directly from its library, Modelsim loads without any problems. I cannot explain the current behavior, because apparently all necessary components have been compiled correctly and should be available. ![axilite_tb](https://europe1.discourse-cdn.com/flex017/uploads/uvvm/original/1X/8ec4ff931f75ab263ddb7fc9a1d894fd0003ac37.png) It would be great if you could help me on this matter. Thank you. ---
**Author:** ![Marius](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/marius/32/43_2.png) [@Marius](https://forum.uvvm.org/u/Marius)\ **Post date:** [February 9, 2021, 3:13pm UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/2 "2021-02-09T15:13:48Z")
Hi, are you running with Mentor Modelsim or another simulator? Br Marius ---
**Author:** ![ktorkelson](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/ktorkelson/32/66_2.png) [@ktorkelson](https://forum.uvvm.org/u/ktorkelson)\ **Post date:** [February 9, 2021, 3:42pm UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/3 "2021-02-09T15:42:06Z")
Hi Marius, I use ModelSim DE-64 2020.4. Best regards ---
**Author:** ![ktorkelson](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/ktorkelson/32/66_2.png) [@ktorkelson](https://forum.uvvm.org/u/ktorkelson)\ **Post date:** [February 9, 2021, 4:47pm UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/4 "2021-02-09T16:47:55Z")
Hello, here is some additional information. I have observed this problem with the AXI Lite VIP version 2.8.0. Since I’ve now gone back to version 2.7.1, everything works fine. Best regards ---
**Author:** ![cartfjord](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/cartfjord/32/39_2.png) [@cartfjord](https://forum.uvvm.org/u/cartfjord)\ **Post date:** [February 10, 2021, 7:12am UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/5 "2021-02-10T07:12:10Z")
Hi, I have also experienced this bug with the AXI VIP. Could not find any fix yet. I am using Modelsim DE 10.6b. ---
**Author:** ![ktorkelson](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/ktorkelson/32/66_2.png) [@ktorkelson](https://forum.uvvm.org/u/ktorkelson)\ **Post date:** [February 10, 2021, 9:10am UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/6 "2021-02-10T09:10:09Z")
Hi all, I also could reproduce the same behavior with the latest AXI Lite VIP (2.8.1). When I start the test bench with ```auto vsim tb_lib.test_tb ``` the error occurs. ```auto ... # Loading uvvm_vvc_framework.ti_uvvm_engine(func) # Loading bitvis_vip_axilite.axilite_vvc(behave) # ** Fatal: (SIGSEGV) Bad handle or reference. # Time: 0 ns Iteration: 0 Process: /test_tb/axilite_vvc_1/read_address_channel_executor File: D:/tmp/uvvm_test/axilite/uvvm/script/../bitvis_vip_axilite/script/../src/axilite_vvc.vhd # FATAL ERROR while loading design # Error loading design ... ``` Contrary, starting the AXI Lite VIP alone with ```auto vsim bitvis_vip_axilite.axilite_vvc ``` Modelsim loads without any problems. Maybe this input can help to solve this issue. Thanks & best regards ---
**Author:** ![Marius](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/marius/32/43_2.png) [@Marius](https://forum.uvvm.org/u/Marius)\ **Post date:** [February 10, 2021, 11:05am UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/7 "2021-02-10T11:05:09Z")
Thank you for the extended information. I will have to test with a DE version and do some debugging. - will notify you when I have a fix. Br, Marius ---
**Author:** ![jorgenkrohn](https://avatars.discourse-cdn.com/v4/letter/j/c77e96/32.png) [@jorgenkrohn](https://forum.uvvm.org/u/jorgenkrohn)\ **Post date:** [February 18, 2021, 3:10pm UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/8 "2021-02-18T15:10:26Z")
Hi, We have found a workaround for this issue. It will be included in the next release. This issue has also been reported earlier. See [https://github.com/UVVM/UVVM/issues/118](https://github.com/UVVM/UVVM/issues/118) where you can also find example code that can be used until the next release. Regards, Jørgen ---
**Author:** ![ktorkelson](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/ktorkelson/32/66_2.png) [@ktorkelson](https://forum.uvvm.org/u/ktorkelson)\ **Post date:** [February 18, 2021, 5:12pm UTC](https://forum.uvvm.org/t/inexplicable-behavior-of-the-axi-lite-vip-in-modelsim/146/9 "2021-02-18T17:12:27Z")
Hi Jørgen, hi all, thank you for your efforts and your great support. I exchanged the two files you mentioned, and now I can get my simulation successfully started. Thanks for your help and your great work you all are doing! Best regards