Altera Corporation iii
Contents
About this User Guide .............................................................................. v
How to Contact Altera .............................................................................................................................. v
Typographic Conventions ...................................................................................................................... vi
Chapter 1. Low-Level Primitive Design
Introduction ............................................................................................................................................ 1–1
Low-Level Primitive Examples ........................................................................................................... 1–2
LCELL Primitive ............................................................................................................................... 1–2
Using I/Os ......................................................................................................................................... 1–6
Using Registers in Altera FPGAs ................................................................................................... 1–7
Creating Memory for Your Design ................................................................................................ 1–9
Look-Up Table Buffer Primitives .................................................................................................1–13
Chapter 2. Primitive Reference
Primitives ................................................................................................................................................ 2–1
ALT_INBUF ...................................................................................................................................... 2–1
ALT_OUTBUF .................................................................................................................................. 2–3
ALT_OUTBUF_TRI .......................................................................................................................... 2–6
ALT_IOBUF ....................................................................................................................................... 2–8
ALT_INBUF_DIFF ......................................................................................................................... 2–11
ALT_OUTBUF_DIFF ..................................................................................................................... 2–13
ALT_OUTBUF_TRI_DIFF .............................................................................................................2–14
ALT_IOBUF_DIFF .......................................................................................................................... 2–19
ALT_BIDIR_DIFF ........................................................................................................................... 2–22
ALT_BIDIR_BUF ............................................................................................................................ 2–25
LCELL .............................................................................................................................................. 2–27
DFF ................................................................................................................................................... 2–28
CARRY and CARRY_SUM ........................................................................................................... 2–29
CASCADE ....................................................................................................................................... 2–30
LUT_INPUT .................................................................................................................................... 2–31
LUT_OUTPUT ................................................................................................................................ 2–32
Synthesis Attributes ............................................................................................................................ 2–33
