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Altera_Forum's avatar
Altera_Forum
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16 years ago

need help with my own peripheral device

I have finished writing a peripheral device. it communicates with niosII cpu using avalon-mm bus. but when i read from it, i can't get the value i want. and writing to it also has no effect on...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

When you build an SOPC component, signals are active high, except if you add '_n' to the name. i.e. if you call your reset signal 'reset', then it is active high. If you call it 'reset_n', then it is active low, and SOPC builder will invert the signal for you.

I prefer to use active high signals when I can, and when I don't/can't, I always add a _n to the name, even if I'm not working with SOPC builder. In my opinion using things like "if reset = '0' then" is less intuitive and makes code more difficult to maintain.