CAS BACnet Stack - BACnet Network Communication | Chipkin Automation Systems

Intro to the BACnet Stack

BACnet is a communications protocol for Building Automation and Control (BAC) networks that leverage the ASHRAE, ANSI, and ISO 16484-5 standard protocol. It is currently the most popular protocol use in Building Automation systems (BAS).

Chipkin’s BACnet Stack (CAS BACnet Stack) is a software library that allows you to add a native BACnet interface to your embedded devices or applications. The BACnet stack supports both BACnet server (Field device, power meter, gas detector, etc.) and BACnet client (HMI, Utilities, data loggers, etc.) services giving you the flexibility you need to succeed. The Chipkin BACnet Stack supports the protocol revision 19, making it a global market leader and one of a few stacks that support's revision 19. Chipkin attends plugfest annually and as of 2018 plugfest, our stack is one of the most up to date stacks in the market.

The BACnet Stack is a transport layer independent library, making it easy to use with any transport layer such as MSTP, IP, Ethernet and even PTP and ARCnet. By giving you control of the transport layer you can optimize bandwidth and performance by exploiting the resources at your disposal such as multi-threading and multiple simultaneous connections. See the diagram below of the BACnet Stack Layers which shows what portions are provided by the stack and what by the client:

             *Area in the border is provided by the BACnet Stack. The area outside is provided by the client.

Benefit from our 20+ years of BACnet experience!!!

Take it from us, we have been working with BACnet for 20+ years. Our BACnet Stack Resume includes 10+ years of development, 25,000+ commits, 50,000+ lines of code, 2,500 unit tests, 50+ devices using the stack and among other capabilities, 1,000,000+ device installations. We know what we are are doing. On top of that, we are also part of the BACnet Testing Laboratory Working Group. Purchasing the BACnet Stack from us will save you man-years of development when your company needs it the most. Let us handle the grunt work, BACnet Spec is complex and it takes months of work just to learn the details.

Chipkin’s BACnet Stack (CAS BACnet Stack) is an application layer BACnet library for embedded systems and application development. The stack allows applicable devices to communicate using several of the BACnet flavors and can function both as a server (Field Device, etc…) or as a client (HMI, etc…).

Because we have also built the stack to be BACnet spec compliant (we do things according to the BACnet spec.), No device that used our BACnet stack has ever failed to receive the BTL Certification (BACnet International BLT) by the BACnet Testing laboratories. We do things the right way from the start!

To ensure our BACnet stack is well tested and compatible with industrial leaders, Chipkin attends the yearly BACnet Plugfest to test new features and services from all of the leading manufacturers.

Furthermore, the CAS BACnet Stack is particularly well-suited to most contemporary programming styles as the API uses XML to transfer requests for packet building as well as for handling back-parsed packets.

  • Supports both BACnet server and BACnet client functionality.
  • Network layer independent supporting; BACnet IP, BACnet MSTP, and other BACnet network flavors.
  • Interfaces to a wide array of different programing language. C, Python, C#, Java, Delphi, Node.JS, etc...
  • Support Protocol Revision 19.
Features Continued
  • Supports Windows, Linux, MacOS, RTOS, and embedded platforms.
  • Supports decoding BACnet messages as XML.
  • Supports BBMD, and Foreign device registration.
  • Designed for maximum portability across a wide range of different architectures and operating systems. X86, 32-bit, 64-bit, ARM, AVR, Microchip, Freescale ColdFire, etc…
  • Supports a wide range of compilers. GCC, Microsoft Visual C++, Borland C++, Code Warrior, IAR, CrossWorks, MicroChip MPLab.
  • Need More Features, Contact us!!

Source Code and Code Quality

Chipkin's BACnet Stack source code conforms to the C++98 standard and is built for portability to many different operating systems and architectures.

Extensive unit tests have been written for our BACnet Stack in Google's C++ test framework. The source code has been tested with Valgrind to detect any memory leaks, threading issues, and performance profiling.

The CAS BACnet Stack is thread safe and can be used on systems that do not support threading.

The CAS BACnet Stack source code has been compiled and tested with the following compilers:

The CAS BACnet Stack interfaces support building applications in your preferred programing language:

Other compilers and programming languages may be supported as well. Please Contact Us for more information

Example Source Code

Please Read the License Agreement before downloading the Sample Code.

See below for a simplified example of creating a BACnet IP server.

Supported Architectures and Operating systems

The CAS BACnet Stack is designed for maximum portability and compatibility with as many different architectures and operating systems as possible.

The CAS BACnet Stack uses a series of callbacks for accessing operating systems and network functionality. An operating systems Interface has been created for the standard operating systems such as Windows, Linux and RTOS and can be ported to other operating systems and embedded systems. Our BACnet stack can be considered network layer and operating systems independent.

As of 2019, the CAS BACnet Stack supports the protocol revision 19, making it a global market leader and one of a few stacks that support's revision 19. Chipkin attends plugfest annually and as of 2018 plugfest, our stack is one of the most up to date stacks in the market.

Operating systems Interface have been created for the following OS:

The CAS BACnet Stack has been ported to many different architectures. Below is a list of all tested functional architectures.

  • Intel x86, 32-bit, 64-bit
  • AMD 32-bit, 64-bit
  • ARM (ARM Cortex-M4, ARMv7E-M, etc…)
  • Microchip
  • AVR
  • Freescale ColdFire
  • Raspbery PI 2/3/4/Zero, Beaglebone, etc...

Porting to other systems and architecture is supported.

BACnet services supported!

The CAS BACnet Stack supports more BIBBs than almost any other BACnet Stack on the market.

Supported BIBBs:

  • DS-RP-A: Data Sharing - ReadProperty-A
  • DS-RP-B: Data Sharing - ReadProperty-B
  • DS-RPM-A: Data Sharing - ReadPropertyMultiple-A
  • DS-RPM-B: Data Sharing - ReadPropertyMultiple-B
  • DS-WP-A: Data Sharing - WriteProperty-A
  • DS-WP-B: Data Sharing - WriteProperty-B
  • DS-WPM-A: Data Sharing - WritePropertyMultiple-A
  • DS-WPM-B: Data Sharing - WritePropertyMultiple-B
  • DS-COV-A: Data Sharing - Change Of Value-A
  • DS-COV-B: Data Sharing - Change Of Value-B
  • DS-COVP-A: Data Sharing - Change Of Value Property-A
  • DS-COVP-B: Data Sharing - Change Of Value Property-B
  • DS-COVU-A: Data Sharing - Change Of Value Unsubscribed-A
  • DS-COVU-B: Data Sharing - Change Of Value Unsubscribed-B
  • DS-V-A: Data Sharing - View-A
  • DS-AV-A: Data Sharing - Advanced View-A
  • DS-M-A: Data Sharing - Modify-A
  • DS-AM-A Data Sharing - Advanced Modify-A
  • T-VMT-I-B Viewing and Modifying Trends-Internal-B
  • T-VMT-E-B Viewing and Modifying Trends-External-B
  • DM-DDB-A Device and Network Management - Dynamic Device Binding-A
  • DM-DDB-B Device and Network Management - Dynamic Device Binding-B
  • DM-DOB-A Device and Network Management - Dynamic Object Binding-A
  • DM-DOB-B Device and Network Management - Dynamic Object Binding-B
  • DM-TS-A Device and Network Management - TimeSynchronization-A
  • DM-TS-B Device and Network Management - TimeSynchronization-B
  • DM-UTC-A Device and Network Management - UTCTimeSynchronization-A
  • DM-UTC-B Device and Network Management - UTCTimeSynchronization-B
  • DM-OCD-A Device and Network Management - Object Creation and Deletion-A
  • DM-OCD-B Device and Network Management - Object Creation and Deletion-B
  • DM-ANM-A Device and Network Management - Automatic Network Mapping-A
  • DM-ADM-A Device and Network Management - Automatic Device Mapping-A
  • DM-MTS-A Device and Network Management - Manual Time Synchronization-A
  • NM-FDR-A Network Management - Foreign Device Registration-A
  • GW-EO-B Gateway - Automatic Device Mapping-A

Supported BACnet device profiles:

  • B-ASC: BACnet Application Specific Controller
  • B-SA: BACnet Smart Actuator
  • B-SS: BACnet Smart Sensors
  • B-GW: BACnet Gateway

Supported services:

  • Who-Has
  • I-Have
  • Who-Is
  • I-Am
  • Read-Property
  • Read-Property-Multiple
  • Read-Range
  • Write-Property
  • Write-Property-Multiple
  • Device-Communication-Control
  • Reinitialize-Device
  • Create-Object
  • Delete-Object
  • Time-Synchronization
  • UTC-Time-Synchronization
  • Subscribe-COV
  • Subscribe-COV-Property
  • Confirmed-COV-Notification
  • Unconfirmed-COV-Notification
Requirements and dependency

The CAS BACnet stack is designed to have minimum requirements to maximize the portability of the source code across as many platforms and architectures as possible. It has the ability to run on devices with very low resources by disabling BACnet services to reduce the required resources and dependencies.

Minimum Requirements:

  • A relative millisecond timer
  • C++ compiler
  • Standard Template Library (STL)
  • Networking: UDP for BACnet IP or RS485 Serial for BACnet MSTP

The amount of ram that the Chipkin BACnet stack requires depends on several factors including; BACnet Services supported, Object types supported, Object count, COV limits, etc...

BACnet objects supported

Our BACnet stack fully supports most commonly used BACnet objects, and partially supports some of the rarely used, advanced BACnet objects. See list below:

  • Analog Input
  • Analog Output
  • Analog Value
  • Averaging
  • Binary Input
  • Binary Output
  • Binary Value
  • Device
  • Multi-state Input
  • Multi-state Output
  • Multi-state Value
  • Character String Value
  • DateTime Value
  • Large Analog Value
  • BitString Value
  • OctetString Value
  • Time Value
  • Integer Value
  • Positive Integer Value
  • Date Value
  • Network Port
  • Elevator Group
  • Lift
  • Escalator
  • Trend Log
  • Calendar
  • Command
  • Event Enrollment
  • File
  • Group
  • Life Safety Point
  • Life Safety Zone
  • Loop
  • Notification Class
  • Program
  • Pulse Converter
  • Schedule
  • Access Door
  • Event Log
  • Load Control
  • Structured View
  • Trend Log Multiple
  • Access Point
  • Access Zone
  • Access User
  • Access Rights
  • Access Credential
  • Credential Data Input
  • DateTime Pattern Value
  • Time Pattern Value
  • Date Pattern Value
  • Network Security
  • Global Group
  • Notification Forwarder
  • Alert Enrollment
  • Channel
  • Lighting Output
  • Binary Lighting Output
  • Timer
  • Accumulator
BACnet BTL Pre-Testing Services

Sending a new BACnet device to the BACnet Testing Laboratory (BTL) for certification can be a daunting task. Each issue or error that BTL discovers thought the testing process will add variable costs and delays. Depending on how long it takes your team to resolve the issues discovered during testing you may be bumped from your testing slot and have to wait for the next available testing slot.

Take it from us, we have been working with BACnet for 20+ years. Our BACnet Stack Resume includes 10+ years of development, 25,000+ commits, 50,000+ lines of code, 2,500 unit tests, 50+ devices using the stack and among other capabilities, 1,000,000+ device installations... Read More!


Purchase any BACnet product from us and we will help you test and document the BACnet interface by providing a free full license to the CAS BACnet Explorer and a Hardcopy of the BACnet booklet.

The USB key and booklet ships with the FieldServer.

BACnet for Field Technicians (Free!)

Learning about BACnet? Want to update your BACnet knowledge? This free EBook will guide you through basic and advanced BACnet topics.

You can purchase a hardcopy of this book from Amazon or you can download the BACnet for Field Technicians for free from our website.

CAS BACnet Explorer

CAS BACnet Explorer is the perfect utility for testing, debugging and discovering BACnet® networks and devices. It is great for network diagnostics and discovering who is the problem. No more pointing fingers.

CAS BACnet Explorer performs the following functions within BACnet Networks:

  • Exploring/Discovering
  • Testing
  • Debugging
  • Monitoring

Buy the CAS BACnet Explorer!!

CAS BACnet Object Monitor

The CAS BACnet Object Monitor is a software designed to run on a Windows computer for testing a connection to a BACnet IP device or to monitor a BACnet IP device.

Its simple to use and FREE! (No email required)

Download the BACnet Object Monitor FREE!!