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Altera_Forum
Honored Contributor
Honored ContributorTwo's Complement and Floating Point
Hello,
I have a range of integer values coming into my system in a two's complement format (positive and negative values). I run these through the altfp_convert module to make these integers floating point values. I do various mathematical operations with them, using other altfp modules. At the end, I use the altfp_convert to return the floating point to an integer to be written out. I wanted to confirm that this conversion does not create a two's complement number, but a signed integer instead. I require a two's complement format to send out, and I wanted to make sure that I would have to change the output of the altfp_convert module. Thanks!3 Replies
Altera_ForumThe output is a 2s compliment number - 2s compliment is a signed format - ie. MSB tells you the sign.
- Altera_Forum
Sure, I've just noticed that I don't see the leading ones that I'd expect in a negative two's complement number.
- Altera_Forum
Then I suspect the output is always +ve
Is there any reason you're using floating point? it's very costly to implement in terms of logic and latency. Fixed point is much cheaper.
