About Stratix 2/4 GX pre-emphasis.

[Altera_Forum]

Stratix 2 GX pre-emphasis has three parameters: pre-tap, 1st post-tap and 2nd post-tap. 

I don't find their meaning in their handbook or in Altera website. Which parts of the output wave is opposite to pre-tap/1st post-tap/2nd post-tap respectively? Thanks.

[Altera_Forum]

i asked someone and your pre-tap is correct, 1st post-tap is correct but not the 2nd post-tap. the 2nd post-tap is twice the width of your 1st post-tap (same starting position at the transition). 2nd post-tap is twice (2 bits) wide. Each tap is 1 bit wide. 

Hope this is right.