Embedded Asterisk and the Blackfin Processor

Topics

• Introduction

• Why Embedded?

• IP PBX Hardware 101

• Free Telephony Project and Open Hardware

• Status

• The Future

• Opportunities

Introduction

• Paradigm shift away from x86/PCI cards

• Embedded = IP-only and no DSPEcho cancellation and codecs not possible

• Analog Devices Blackfin Processor has the potential to change this situation

Why Embedded

• Small size (DSL router)

• Low power < 10W (battery, solar)!

• No moving parts (fans or disks)

• Quiet

• Reliability (parts count, connectors)

• Low cost (a few hundred $ street)

• Just plain cool!

Blackfin Processor

• A powerful DSP (1 GMAC)

• AND runs uClinux

• Breaks the two processor (host/DSP) paradigm

• Low cost ($5 - $15 each)

• Well supported by vendor and community

• Open hardware and software

IP-PBX Hardware 101

PCI Bridge

FXO Port

x86 CPUDSP

hardware

Asterisk

Ethernet Card

FXS Port

Host PC PCI Card

Device Driver

IP-PBX Hardware 101

FXO Port

Blackfin CPU

DSP software

Asterisk

Device Driver

FXS Port

Embedded PBX

IP-PBX Hardware 101

• Many redundant parts removedLower costSmaller sizeLower powerEnhanced reliability

• Don’t need “hardware” DSP – Blackfin CPU is a DSP

Challenges

• Complex development environment– Cross compiler & tool-chain – Customized kernel and apps

• Learning Curve

• Low memory ~64MB

• uClinux (offset by partial MMU)

• Care and feeding of the cache

Who is working on Blackfin Asterisk?

• Several individuals and companies (e.g Digium) working on Blackfin Telephony products

• Expect to see many Blackfin based Telephony products in the near future

• This presentation focuses on the activities of the Free Telephony Project

Free Telephony Project Goals

• Build a completely open embedded telephony platform.

• Hardware designs are open.

• Full design and manufacture information available for download. Schematics, PCB layouts, HDL code, unit tests

Motivation

• Various motivations across the people and companies involved in the project.

• Obvious business potential in a $200 IP-PBX with multiple ports.

• Enabler for service models.

• My motivation is Social & Geeky rather than Business.

Motivation

• I like building stuff• Would like to use my hardware/DSP skills

to improve the world a little• Open software like Linux and Asterisk has

been a great thing for the World.• Craig Newmark (Craigslist) : Nerd values

“Get yourself comfortable, then do something fun to change the world a little”

Open Hardware

• The designs are free as in speech

• A community exists that are sharing designs and helping each other.

• Build better hardware faster using open development models.

• Opportunities for small business.

• It’s working!

Hardware Projects (so far)

• Motherboard plus stackable daughter card architecture

• Various 4-8 port Analog interfaces

• Blackfin Motherboard with dual Ethernet + USB

• E1/T1

• Quad BRI-ISDN (8 channels)

How to Hack Telephony Hardware in Linux

• Schematic Entry (gschem)

• PCB Design (PCB)

• Verilog HDL (Icarus)

Port Asterisk to Blackfin

(gcc)

Design Schematics (gschem)

Design PCBs (PCB)

Assemble Prototype Hardware

Debug and Test Hardware

Write Verilog Code (Icarus)

Integrate and Test system

Design Process Flow

gschem Schematic Entry

Analog Hardware Example

Status

Port Asterisk to Blackfin

Develop Analog

Hardware

Integrate and Test PoC System

Type Approval

Volume Manufacture

Build and Test Beta Units

Port driver to Blackfin

Sep 2005 Dec 2005 Sep 2006

Oct 2006

Q1 2007

Status

• Asterisk ported to the Blackfin

• Stable but Beta

• FXO/FXS hardware designed and being beta tested

• Beta hardware available for sale now

• Undergoing compliance testing

• Commercial (open) hardware in Q1 2007

Performance

• 500 MIPs Available (1 GMACs)G729A (10 MIPs)Speex (15-30 MIPs)

• Simultaneous SIP Calls (approx 50)

• Echo CanDepends on tailSay 12 with full 128ms, 24 for FXS

Opportunities

• Business

• Individuals

• End Users

Opportunities for Business

• Massive Differentiation

• Cost/Margin advantages

• New products we haven’t even thought of:Asterisk ATA or faxAsterisk in an very smart IP-phoneT1 IP-PBX in an ATA form factor for $200?

Opportunities for Individuals

• It’s open. All of it. Hardware and software. Even the CAD tools!

• Exciting project in early stages

• Chance to really contribute

• It’s very different from x86/PCI

• Helped needed: Hardware, software, Asterisk config

Opportunities for End Users

• Lower end user cost – a $300 (street) 4-port IP-PBX in 2008?

• IP-PBX functionality in the home rather than current ATA.

• Bring telephony to developing countries.• Small, fan-less lets you reach markets like

SOHO that don’t want a PC for their phone system.

Getting Started

• Buy a Blackfin STAMP Card ($226)

• Buy a 2 FXO 2 FXS port Analog Starter Kit ($299)

• Start Hacking

Questions?

For more information

http://www.rowetel.com/ucasterisk

Geda

blackfin.uclinux.org