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Re: Serial connecting PLC on Alpha1200 TTA0

 
Anton van Ruitenbeek
Trusted Contributor

Re: Serial connecting PLC on Alpha1200 TTA0

@Hakan
The PLC is never logging in, its machinery.

@Bob
I've found in the documentation that the TT driver behaves quite difference than the LTA driver.
If whe change this program by modifying the behavior and check for TT or LTA port, I also (my opinion) need to change the other programs. Because the interfaces are probably changing there as well.

@Hoff
This is exactly what happend (I think). The PLC sends a 'NACK' (%X15) when it doesn't understand the message send (which needs to start with a 'ST'-bit (%X2)). But the strange thing what was happening is that previous the situation was that the machines booted up with the PLC on TTA0 and the behaviour was the same.

@DEXchange
Thanks for the code checking.

To all,
We (costumer and I) decided to not change the code (for this part) and go for the terminalserver solution. I mentioned the other PLC's in the hall and there are still some ports free on the terminalservers on the floor.
Only this PLC is ended in the computerroom (optical etc.) and here are no terminalservers.
The final will be that 1 terminalserver will be mounted with one port connected to this PLC endpoint. In the future we will try to move all the other connected PLC's to the computerroom.

Thanks for all of your input and thoughts.

AvR
NL: Meten is weten, maar je moet weten hoe te meten! - UK: Measuremets is knowledge, but you need to know how to measure !
Jon Pinkley
Honored Contributor

Re: Serial connecting PLC on Alpha1200 TTA0

Anton,

I think you have made the correct choice: Keep everything as similar as possible. Since you are successfully using terminal servers other places, using them everywhere is best from a support standpoint.

Good luck,

Jon
it depends