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The configuration of Tags for generic commands is a special functionality of this Driver that allows programming a command directly using an EAP code defined by a manufacturer. Thus, any other commands not defined by a manufacturer can be executed, as long as information about these commands are provided by Agridatalog srl. This also includes devices created in the future and use the EAP serial protocol for communication.

Users can use PLC or Block Tags, depending on the amount of information a command requires. The interpretation of N or B parameters is relative to fixed commands per device, according to the next table.

 

 

The N2 or B2 parameter must be filled with a code that ranges between 0 (zero) and 255 (or FFFFh in hexadecimal notation). The N4 or B4 parameter must be filled with the next information:

•Number of bytes to receive or send by a command, between 0 (zero) and 255

•Permission for a command to read or write, a fixed value equal to 256

 

If a command is for reading and writing, sum the number of bytes to receive to the fixed value of 256. For example, if the total number of bytes to receive is equal to 8 (eight), the value of the N4 parameter must be equal to 264.

The indication of reading and writing of a command can be omitted when performing only readings in a Tag for a reading and writing command or if a command allows only reading or only writing.

 

 

The next information contains important considerations about the configuration of Tags for generic commands.

 

In Case of Reading

•When informing the reception of 1 (one), 2 (two), or 4 (four) bytes, the value read can be configured in a PLC Tag or a Block Tag with a single Element. For other values, create a Block Tag with the number of Elements equal to the number of bytes to receive, because each Element read a byte from the response of a command

•Informing a value 0 (zero) to the number of bytes to receive is not allowed

•The maximum value of bytes to receive is 255

 

In Case of Writing

•When informing the transmission of 1 (one), 2 (two), or 4 (four) bytes, the value sent is in the Value property of a PLC Tag or in the Value property of the first Element of a Block Tag. When informing the transmission of 6 (six) bytes, typical of writing a date-and-time value, each Element of a Block Tag with 6 (six) Elements contains the value of these bytes for transmission

•Users can inform a value 0 (zero) for the number of bytes to send, because there are commands that do not need to send values

•Values different from 0 (zero), 1 (one), 2 (two), 4 (four), and 6 (six) for the number of bytes to send are not supported for writing

 

For example, for a T1MIN command from a Cellostat CS950A/G device, users have the following values:

•EAP code: 20h

•Size of information: 2 (two) bytes

•Permission: Reading and writing

 

To express that command in a generic way, consider that this is an information with a size of 2 (two) bytes. Therefore, users only need a PLC Tag with the N1 parameter equal to 4 (four), the N2 parameter equal to 32 (20h in hexadecimal), the N3 parameter with the address of a destination device, and the N4 parameter equal to the sum of value 256, which indicates a reading and writing permission, with the value of 2 (two) bytes to receive or send. Thus, the N4 parameter must be equal to 258.

Indexes for models of devices

 

List of commands for Cellostat CS950A/G devices (the N1 or B1 parameter equal to 0)

 

List of commands for Agri Controller 2500 devices (the N1 or B1 parameter equal to 1)

 

List of commands for Econom (EC55/EC100) devices (the N1 or B1 parameter equal to 2)

 

List of commands for Sequencer (CMP8/16/4+4GL/2+2GL) devices (the N1 or B1 parameter equal to 3)