Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
21 years ago

[Nios II]: questions on "trap" and modelsim

Hi, I started to use the "Nios II/fast core" and made some timing tests. but I got some trouble to find out how "trap" work. in assembly, when user issue a trap: .... tra...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
21 years ago

Hi Jesse,

Yes I saw the part of multiplication/division emulation. But in this case the branch is done automaticaly by the nios (exception interruption not implemented). So in the code, there are nowhere the instruction trap. right?

If right, I wonder what the point of having a "trap" instruction is. Is is done so that the user can put a "trap" in his own code?. The only meaning I see, is if the user wants to make a function call, that would be executed in supervisor mode (trap changes mode to user mode)??

Sorry, I got a lot of question, I just started to study the Nios for a few days, but it seems really cool http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/smile.gif !

By the Way, I saw you are working at Altera. Is this forum altera-official? anyway, it&#39;s a really good idea:) Thanks you a lot for your responses

Sylvain,

...missing california...