GE Ethernet Global Data

9 min

Review the following information for setting up and configuring the GE Ethernet Global Data (EGD) Ethernet driver.

Ethernet Global Data is a publish and subscribe protocol. A controller publishes a block of data called an exchange at a fixed rate, and any device on the network configured to consume that exchange receives it. Litmus Edge (LE) works in both directions. Consumer tags read data from exchanges that a controller produces, and Producer tags contribute data to an exchange that LE produces.

The driver connects on port 18246 by default. It does not support device discovery or tag browsing, so you enter the network and exchange details manually.

Note: This driver is experimental. Some features may not work as expected.

Compatibility

Compatibility Parameter	Compatible Items
Driver Type	Ethernet
Validated Devices/Series	GE devices that support EGD transactions and use CPU-364 or higher

How to configure the PLC

To set up and configure this device in Litmus Edge, you will need to do the following:

Step 1: Set up and configure the PLC device

Step 2: Set up the PLC device in Litmus Edge DeviceHub

Step 3: Configure the list of registers

Step 1: Set up and configure the PLC device

Confirm that the controller supports EGD transactions and uses CPU-364 or higher.

Configure the exchanges the controller produces, and note the exchange ID and the size of each one.

Note the controller's IP address. You enter it as the Producer ID on each Consumer tag.

Identify the network interface on the LE system that reaches the controller, and note its address and subnet mask.

Note: The driver does not support device discovery or tag browsing. Enter every value manually.

Step 2: Set up the PLC device in Litmus Edge DeviceHub

Configure the following parameters when you Connect a Device with this driver. Update default values to the specific setup of your device.

Parameter	Value
Type	GE Fanuc
Driver	GE EGD Ethernet
Name	Enter a name for the device. Default: ge-egd-ethernet_device.
Description (Optional)	Enter a description for the device.
Network Interface	Enter the address and subnet mask of the LE network interface that reaches the controller, in CIDR notation.
Network Port	Enter the EGD port, from 0 to 65535. Default: 18246.
Producer Exchange Destination	Enter the destination address for the exchange that LE produces. Default: 192.168.0.1.
Producer Exchange ID	Enter the ID of the exchange that LE produces, from 1 to 65535. Default: 1.
Producer Exchange Size	Enter the size in bytes of the exchange that LE produces, from 1 to 1400. Default: 1.

Note: The three Producer Exchange parameters describe the exchange that LE publishes. Set them only if you add Producer or Producer Bits tags.

Step 3: Configure the List of Registers

When you Add a Tag to the connected device, refer to the following register table and tag parameters. Refer to the following additional resources:

Organize Device and Tag Data by Using Metadata

Tag Formula Variables

Register table

Select the register name in the Name list, then supply the address. Consumer registers read from an exchange that a controller produces, so they also need a Producer ID and an Exchange ID to identify which exchange to read. Producer registers write into the exchange that LE produces, which you configured in Step 2, so they need no producer details.

The Address range depends on the register. Bit registers accept 0 to 11199. Word registers accept 0 to 1399.

Name	Value Types	Access Types	Description
Consumer	uint8, uint16, uint32, uint64, int8, int16, int32, int64, float32, float64	R/O	Reads a value from an exchange produced by a controller.
Consumer Bits	bool	R/O	Reads a bit from an exchange produced by a controller.
Producer	uint8, uint16, uint32, uint64, int8, int16, int32, int64, float32, float64	R/W	Contributes a value to the exchange that Litmus Edge produces.
Producer Bits	bool	R/W	Contributes a bit to the exchange that Litmus Edge produces.

Tag parameters

Parameter	Value
Name	Select a register name from the drop-down list. Available options depend on the names in the register table.
Value Type	Select a data type from the drop-down list. Available options depend on the register name selected.
Producer ID	Enter the IP address of the controller that produces the exchange. This parameter applies to Consumer and Consumer Bits registers.
Exchange ID	Enter the ID of the exchange to consume, from 1 to 16383. Default: 1. Together with the Producer ID, this identifies which messages to consume. This parameter applies to Consumer and Consumer Bits registers.
Address	Enter the offset within the exchange. Default: 0. For Consumer Bits and Producer Bits, the range is 0 to 11199. For Consumer and Producer, the range is 0 to 1399.
Count	Enter the number of values to read, from 1 to 65535. Default: 1. A count higher than 1 generates an array of values from the address configured and the addresses that follow it.
Tag Name	Enter a name for the tag.
Description (Optional)	Enter a description for the tag.
Tag Formula	Enter a formula to process tag data. See Tag formula below.
Only Publish on Change of Value	Select the checkbox to publish NATS messages only when the value parameter changes to a new value. Change of Value only applies to boolean, numeric (such as int or float), and simple string data types. It does not apply to complex types, such as JSON or array. Poll-once topics are not affected by Change of Value settings. These topics will still only see a single message.
Meta Data	Metadata summarizes basic information about data. This feature allows you to define key-value pair data for the device output payload later on. It can then be used to find, use, and reuse particular instances of data. Note: If you use special characters in meta data key names, the special characters are replaced with underscore characters in the payload. This can cause two key names to be combined into one. For example, configuring the key names a**b and a&&b will cause only one key name to be created (a__b).

Note: This driver has no Polling Interval parameter. EGD data arrives when the producing controller publishes an exchange, so the controller sets the rate.

Tag formula

Enter a formula for the tag to process the generated data. Two variables are permitted: value (current tag value) and timestamp (current tag UNIX time in milliseconds). The following math functions are available:

Function	Description
sin	Sine
cos	Cosine
sqrt	Square root
tan	Tangent
power(x)	Performs the operation 10^x
log(x)	Natural logarithm (base e)
exp(x)	Performs the operation e^x