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Altera_Forum
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14 years ago

NCO help...

Hi i'm trying to test a fixed point filter on a FPGA board, my filter has an input of 16 bit, but the maximum value it can take without saturation is 1023 which is 11 bits. so far the only signal i'v...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

You must look at values displayed as 2's complement only then make your judgment.

Since you have extra sign bit you will get false -2048 on 12 bits bus if viewed as sign and magnitude.

1111 1111 1111 means -2047 in sign and magnitude.

1100 0000 0000 means -1024 in 2's complement