Nimodbus examples

[azertyuiop]

Hi all, I'm trying to communicate from a PC to a frequency controller with the Modbus protocol, using a serial port. I use Labview 8.0 (and I'm a beginner!). I tried to run the example from the nimodbus.llb library, connecting two serial ports of the PC, with a null serial cable. One port is the master and the other is the slave. The slave VI and the master VI are running correctly, it doesn't return errors. However, no information circulates between the both ports. Ports are working and the cable too. Anyone could help me? Thanks Elsa

[ChristopheS.]

Hi,

When you try the example, have you start the slave in first, and the master in second ?

Because you need follow this order.

Regards,

[azertyuiop]

Hi,

Yes, it was in the instruction. It seems to be clear that the both serial port don't see each other, however each port works correctly and the cable too.

Regards,


Elsa

[ChristopheS.]

I think you have configured correctly the two serial port ?

_ Same baud rate

_ Same databits

_ Same parity

_ Same stop bits

And used a crossover cable ?

regards,

[azertyuiop]

Hi,

I'm really a beginner : I didn't know that I had to use a crossover cable. Thank you very much, now it works.

Elsa