IPBus Builder Tutorial

An essential tutorial to ipbb: How to create and simulate and eventually build firmware projects with ipbb. The examples, increasing in complexity, show how to include source files in a ipbb project by means of dependency files and use them to create vivado or modelsim/questasim projects.

Getting started

Install ipbb locally:

curl -L https://github.com/ipbus/ipbb/archive/v0.3.7.tar.gz | tar xvz
source ipbb-0.3.7/env.sh

Prepare a work are and add the tutorial code to it:

ipbb init tutorial
cd tutorial
ipbb add git [email protected]:alessandrothea/ipbb-tutorial.git

01 - Half adder

A simple 2-bit adder block with testbench.

• Minimal package example, no substructure, no component-project splitting
• Code example from vhdlguide
• half_adder entity: calculates a 2 bit-sum with carry-over.
• half_adder_tb testbench: tests all output values.

ipbb commands

ipbb proj create sim 01_half_adder_tb  ipbb-tutorial:01/half_adder -t half_adder_simple_tb.dep
cd 01_half_adder_tb
ipbb sim make-project
./vsim -novopt work.half_adder_simple_tb

in modelsim/questasim tcl shell

add wave -position insertpoint  \
sim:/half_adder_simple_tb/a \
sim:/half_adder_simple_tb/b \
sim:/half_adder_simple_tb/carry \
sim:/half_adder_simple_tb/sum
run 200ns

02 - Mod Counter

Mod-m counter counts the values from 0 to (m-1). Identical to 01 from ipbb's perspective

• Minimal package, no substructure, no component-project splitting
• Code example from vhdlguide
• modMCounter entity, N-bit counter up to M.
• provided with top-level testbench, modMCounter_tb

ipbb commands

ipbb proj create sim 02_modMCounter_tb  ipbb-tutorial:02/modMCounter -t modMCounter_tb.dep
cd 02_modMCounter_tb
ipbb sim make-project
vsim -novopt work.modMCounter_tb

in modelsim/questasim tcl shell

03 - Full adder

A full adder implementation using 2 half adders.

• 2-components examples. half_adder and full_adder belong to different "components". The testbench is located in a separate folder tests.
• full_adder entity: implements a full 2-bit adder as with 2 half_adders.
• full_adder_tb testbench: tests all output values.

ipbb commands

ipbb proj create sim 03_full_adder ipbb-tutorial:03/tests -t full_adder_tb.dep
cd 03_full_adder
ipbb sim make-project
./vsim -novopt work.half_adder_simple_tb