The information on this web page is either Lynn's opinion or something Lynn agrees with.He has complete control over its contents.Nothing contained within this pages is approved by or represents the opinion of Digi International, The Modbus Organization, the Modbus-IDA Group, ODVA, or any other organization Lynn is associated with.

Lynn's IA Protocol Tips Site (Feb 2007)

• Q: Why is this site here?
• Q: What's new on this site?
• Q: What are common IA Protocol Groups?
• Q: What tools are used by the IA Coffee House?
• Q: How to contact Lynn?

In January 2007 I started porting all my info to a Wiki site iatips.wikispaces.com. A wiki is a database-driven web site that allows teams to work in parallel, including recording changes and allowing them to be rolled back if required. I had started adding some Modbus stuff to wikipedia.org "Free Encyclopedia" - but it is too wild and uncontrolled for me. After a third idiot deleted my "Modicon Modbus Plus is NOT RS-485" comment for the third time I decided that it was a waste of my expertese. Putting iatips.com into a Wiki simplifies my ability to add content and will allow other people to help add to the info. Anyone interested to help or add content, just email me or go to the Wiki and ask to join the team. Jump to the iatips Wiki home

Question? Why is this site here?

Answer: it is a neutral place to discuss CROSS-standard issues.

For example, how can an ODVA Ethernet/IP client poll a Modbus/RTU slave? How can a Modbus/TCP client poll a DeviceNet or FF/H1 device? I consider these questions critical for effective real world integration. Yet if I try to bring up the subject in ODVA or Modbus.Org, it is considered not within the scope of valid discussion (one could ALMOST consider such subjects taboo?). So when 20 vendors create CIP objects to access a Modbus slave, we end up with nothing publicly useful - just 20 different vendor-specific objects. But there is no reason we cannot define some nice psuedo-public objects so that buyers of the 20 vendors' products can end up with the same solutions.

An African proverb: "When elephants dance - the grass gets crushed". People who work for small companies know what it's like to be 'grass'. As the big protocol battles waltz forward, we suffer because we have to implement them ALL! Whether IDA or Ethernet/IP or ProfiNet are 'best' is 100% irrelevant. We must implement all three if we want to have the widest market for our products. Every big vendor with a new idea and the nonprofit corporation they fund 'to save the industrial world' just means more work for us.

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Question? What's new on this site?

To help repeat visitors find new information, see this list of changes

Jan-2007 & beyond: Started porting all my info to a Wiki site. This will allow other people to help maintain and add to the info. Jump to this New Stuff

12-Nov-2006: Added Lynn's Industrial Protocols over IP blog. Jump to this New Stuff

13-Aug-2005: Added info on undocumented SLC5/MicroLogix commands. Jump to this New Stuff

13-Aug-2005: Added an example AB/DF1 read from a MicroLogix. Jump to this New Stuff

10-May-2004: Added discussion of ControlLogix MSG block talking to PCCC slaves. Jump to this New Stuff

01-May-2004: Added example "C" code to show Modbus/RTU estimation of req/rsp length. Jump to this New Stuff

25-Apr-2004: Added discussion of Omron protocols - HostLink and FINS. Jump to this New Stuff

09-Feb-2004: Added discussion of AB/DF1 'Auto-Baud' and 'Auto-CRC/BCC' Detect. Jump to this New Stuff

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Question? What are common IA Protocol Groups? Here are a few of the more common web site related to Industrial Automation.

• Rob's Fieldbus Pages is the best link page for protocols
• IDA: Interface for Distributed Automation Group; IEC 61499
• Site by chairman of IEC 61499, with Java sample tool
• The Modbus Organization (now Vitamin IDA Enriched!)
• ODVA: Open DeviceNet Vendor Association; DeviceNet & Ethernet/IP
• ProfiBus & ProfiNet
• Foundation Fieldbus
• HART Fieldbus
• OMAC: Open Modular Arch Controls
• FAOP: Japanese Standard for Ethernet
• CCLink: Japanese Fieldbus Std
• ASI bit-bus
• CAN info

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Question? What tools are used by the IA Coffee House?

Editable Documents: This is the year 2003, so I cannot justify working in simple text files - or using .NROFF macros like they do at IETF. But I also don't want to force anyone to buy Microsoft Windows or Word if they don't have it. So I work in OpenOffice v1.1. It works Ok - makes your computer sweat a bit more than MS-Word. OpenOffice can also export PDF format.

Acrobat Documents: Of course, there will PDF files. I'll try to remember to keep them PDF version 1.2 (Acrobat version 3.0) so older readers can handle them. You can get Acrobat Readers here. OpenOffice exports a simple PDF file, but real Adobe Acrobat does a better job.

Ethernet Traces: Another useful tool is the open source Ethernet tracer Ethereal. If I need to disclose any traces, I'll be using this tool.