Watlow Series 96 driver

[LeifArnesen]

So I have a Watlow 96 connected to my HP laptop (Windows 7) via a RS232 to USB serial adapter.  I am new to LabVIEW and I am having trouble figuring out what driver to install/use to communicate between the two (Watlow and laptop) and figuring out how they communicate with each other.  I have been told to use an NI Serial Driver and have also been told by others to use a Modbus driver.  After making several calls, I am still unclear as to what products I need to purchase to make communication between these two devices possible and also how these products work.  What is the difference between an NI Serial Driver and a Modbus driver?  Where do I download/purchase these drivers?  I also downloaded the watlow-basicndriver.llb from the LabVIEW drivers - Watlow Series 96 controller web page, but I would also like to know how this file comes in to play.  Any assistance would be greatly appreciated.  Please feel free to call as well.

Thank you for your time,

Leif Arnesen
(602) 283-5054

[LeifArnesen]

Can anybody help?

[Dennis_Knutson]

You might want to first get a basic understanding of Modbus such as here. The Modbus protocol can be used over RS232/485 or Ethernet physical layers. With your USB-RS232 converter, you would need to have NI-VISA (from your drivers DVD or a free download) installed to support the physical layer. NI-Serial is only required if you are using an NI converter. The NI Modbus library implements the Modbus protocol so you can communicate to the device. By studying the manual for the Watlow, you should be able to determine which registers and addresses you need to read/write.

The driver you downloaded appears to implement a few specific communication functions for the Watlow. It does not use the more generic Modbus library from NI. There is an example VI that you can try.