HDL FIFO and (not so) algebraic loop errors

2020 9 29
2 个回答
回答已采纳
更新时间：2020 9 30
9 次查看（30 天）

0 个投票

Hi everyone, thanks for checking in on my question.
What I am trying to do is build a sorting network based on mergesort. For every sorting step I use a HDL FIFO Block to store the sorted results. The next sorting node will compare the outputs of wo fifos and togehter with some additional logic decide which value to forward. The corresponding fifo from the layer will be poped according to this decision. Therefor I loop back the pop from one stage to the previous stage.
This lead to an algebraic loop error in his pop signal. I could resolve this by use of an delay, but it will destroy the sorting. I was able to somehow resolve this error for my test setup, but after migrating the concept to my special problem, I could not get it to work again. Do you have any Ideas which settings might be involved in this error, that I might tweak to get it running?
I am sure, that actually there should not be an algeraic loop in the model at all, therefor I have trouble understanding what is going on.
Greetings and thanks in advance
Edit:
Uploaded the software here: https://www.mathworks.com/matlabcentral/fileexchange/80578-sorter-to-sort-4-presorted-datasets

请先登录，再回答此问题。

 采纳的回答

Florian Rössing
Florian Rössing 2020-9-30

0 个投票

Good Morning,
have you ran testbench.m, which should also be in the folder minimalexample? It fills the parameters into the workspace in order to be capable of running the simulink file. I didnt know how to create all this in a simulink function block.

1 个评论
显示 -1更早的评论 隐藏 -1更早的评论

Florian Rössing
Florian Rössing 2020-9-30
OK renaming the INP1_POP and INP2_POP in POP1 and POP2 resolves the issue for reasons i do not understand...

请先登录，再进行评论。

更多回答（1 个）

Kiran Kintali
Kiran Kintali 2020-9-29

1 个投票

Can you share the model with the algberaic loop error? What version of MATLAB and HDL Coder are you currently using? Thanks.

5 个评论
显示 3更早的评论 隐藏 3更早的评论

Florian Rössing
Florian Rössing 2020-9-29
I can not share the full model, as a lot of the peripherals are confidential. But I will try to atleast get the important part out of it.
I am using Matlab R2018a, Simulink 9.1, HDL Coder 5.4.
Kiran Kintali
Kiran Kintali 2020-9-29
A smaller model reproducing algebraic loop issue is sufficient.
Florian Rössing
Florian Rössing 2020-9-29
I have already edited a link with the code into my original post. I will edit the model to get a working example to produce the error.
Florian Rössing
Florian Rössing 2020-9-29
I now have added a minimal example that should be cappable to be run as standalone version. See: https://www.mathworks.com/matlabcentral/fileexchange/80578-sorter-to-sort-4-presorted-datasets in the folder minimalexample
Kiran Kintali
Kiran Kintali 2020-9-29
Thank you. I need a model that does pass update diagram phase (ctrl-d) without initialization issues. It looks like few initialization of variables missing. it would be great if you can show the algebraic loop error.

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 HDL-Optimized System Design 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by