I am trying to write a driver for the Watlow series 96. Any avaliable help?

[gwong]

Are there any example VI's I can take a look at or example code already written in labview?

[Brian_Vibert]

To talk to a Watlow 96 you need a driver that allows you to communicate in Modbus RTU mode. Once you get that working its just a matter of reading and writing to the correct register number. Search the forum archives for Modbus to find some pointers. This message should help get you started: http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=506500000008000000A1350000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0

I could probably dig up the drivers I wrote a while back for the 96. If you want them or you have more questions let me know and I'll be happy to help.

Brian

[gwong]

Thanks for you help. I would like to take a look at those drivers you wrote if you could please send them to me, I'd appreciate it. Thanks.

[Brian_Vibert]

I don't have a full set of drivers, just routines to set and read temperature. In the attached library there is a file called WATReadTemp.vi to read the temperature and WATSetTemp.vi to set the setpoint. They are not very well documented but should help get you started at least. If you have any questions about their operation feel free to let me know.

Hope it helps,
Brian Vibert

[Jim_in_Oceanside]

gwong wrote in message news:<50650000000500000098860000-1023576873000@exchange.ni.com>...
> Thanks for you help. I would like to take a look at those drivers you
> wrote if you could please send them to me, I'd appreciate it. Thanks.
Email me for information about functional Labview Modbus vi's for Watlow model 96.

[gwong]

If you have any additional VI's for the watlow 96, I would appreciate any help you can offer. Also, I have having problems with communicating to my device. I have hooked the 232 cable to the computer wired correctly yet MAX is not detecting the device and therefore I am unable to communicate with the device. Any ideas?

[DougD]

I don't think that MAX would be able to detect it necessarily. It's
not a NI product is it? NI doesn't make MAX to automatically support
everybody's instrumentation automatically. You are only assured that
MAX will recognize your instrumentation if it is NI.

That doesn't mean that you can't communicate with it though.

Do you have the programmers manual? You will need it if you don't
have one. It should give you all you need to know: Cable diagrams,
Baud rate, parity, data bits, stop bits, handshaking protocol, etc.
It should also give you all the command information you need.

The best way to do this is to start out with Hyperterm or Procomm and
try interactively communicating to the device with a few sample
command
s to see if it responds. If it doesn't, verify that you have
the right cable. Often, non standard cable layouts are used.
Sometimes you need a straight through, sometimes a null modem cable.

If you aren't able to get it to talk this way or with a simple LV
program, then try contacting the mfgr to get some help.

Douglas De Clue
ddeclue@bellsouth.net



gwong wrote in message news:<50650000000500000071920000-1027480788000@exchange.ni.com>...
> If you have any additional VI's for the watlow 96, I would appreciate
> any help you can offer. Also, I have having problems with
> communicating to my device. I have hooked the 232 cable to the
> computer wired correctly yet MAX is not detecting the device and
> therefore I am unable to communicate with the device. Any ideas?

[Brian_Vibert]

MAX won't detect it, nor should it. If you have it wired correctly then the VIs that I provided should help get you started. Make sure that you have the baud rate set correctly using the VISA Configure Serial Port. This is really the only way that you can get it to work, Hyperterm or Procomm won't work for you because the Watlow uses binary Modbus which they don't support.

[gwong]

I have set the baud rate correctly but I am a little lost with the program you have sent me. Is there supposed to be an output seen on display? In the 'String received from device' window? Is that a way to tell if my device is communicating with my computer correctly? Thanks again for your help.

[Brian_Vibert]

I'm afraid that I'm not sure what vi you are talking about. You should be able to use the vi called "WATReadTemp.vi" that is included in the library in my earlier post. All you should have to do is set the Comm Port and Address and run the vi. You should then get a number in the Temp indicator that should be the same as the temp indicated on the display of the Watlow96. If you don't get a reading then you have some sort of problem. Hope this helps.