Unistream Modbus limitation

[Ricardo_Oliveira]

Hello Guys,

I have trying a communication with a Unistream as a Slave and I'm having some problems. When I create a program on Unistream with 255 tags, the communication works ok and all address is read but when I add 1 more tag the program don’t work well. The master only can read about 175 address.

 

 

In this case it does not matter the specific address, but the number of tags in the program.

Does Unistream has a limitation on number of adress that can be read? Has anyone already had the same problem?

[Flex727]

IS this MODBUS? There are limitations in the MODBUS standard for register reads.

[Ricardo_Oliveira]

Hi!

Yes, it's Modbus IP and UniStream is a SLAVE. Have you ever had or knew about this problem? Is there a solution to add and read more than 255 address? Because it does not matter the range of addresses you want to read, but the number of tags added, which in this case are limited to 255.

[Flex727]

Break it up into multiple reads.

[Ricardo_Oliveira]

But the Unistream is Slave and the master is read only one tag for example. In this case it does not seem to be a problem with the amount of addresses read, but the amount of tags added in the slave.

[Cam]

As Flex says your going to have to break it up in to multiple reads.

[Ricardo_Oliveira]

Ok guys, thank you for your help.

 

I need to creat an array to read all adresses.

 

Tks