RS-485, -422, & -232

[Kiko-of-Brasil]

I am trying to use version 8 together with a two-port RS-485 card to read six different signal conditioners (load cells).

These conditioners are daisy-chained together and only one cable (phone type) goes into one of the pci board.

I am using the RS-232 input module but there seems to be a mix-up of signals and possibly even some summing of error.  Nothing displayed in DASYLab matches the display in the signal conditioners (Transducer Techniques DPM-3s).

Any suggestions?  Is the RS-232 input the way to go?

Thanks, Kiko

[TomRizzo]

Kiko,

Analo input is always the best wasy to go, if you use the RS232 format, then you need to setup the module correctly.  For that, it will require to have more informationregarding the device you are using.

[Kiko-of-Brasil]

When I try to use an Analog Input, DASYLab says "this module is not supported by the installed hardware."

I know little about computers/electronics so bear with me...

I do get readings using the RS-232 and since the Analog input does not work (neither does the digital), what now?

The idea of using the RS-485 is so we have one input/output for six different readings.  It comes across as if DASYLab is having a hard time sorting things out.

Could it be a driver problem for the board?

Thanks, Kiko

[Kiko-of-Brasil]

here is the board i am using:

http://www.startech.com/item/PCI2S485-2-Port-PCI-RS-422-485-Card-with-DB9.aspx

[TomRizzo]

Kiko,

Sorry for the answer, but I would strongly sugget to find a local DASYLab integrator because I feel that you could solve that problem easier if you had an exepert beside you.

[CJ_Butler__DASYLab_Pro]

Hi Kiko,

Usually RS485 devices require an address with the command and response, so that each device can only respond to its own command. This is a part of the Rs485 multidrop protocol.

When connected to a PC, an RS485 network looks like a comm. port, which is why you are using the RS232 Input module.

What are you using to query each device, and how does it respond?

[Kiko-of-Brasil]

dear CJ:

i am trying again to get back on the saddle here:

in more detail:

i have six devices daisy-chained together via RJ11 cables.  then a single cable from my first device goes into an RS-485 board.

the board being used:  http://us.startech.com/media/products/PCI2S485/Man​uals/PCI2S485.pdf

the devices being used:  http://www.transducertechniques.com/pdf/dpm3.pdf

i am very confortable with dasylab but i am electronically ignorant when it comes to things, like send, receive, addresses, handshakes, and so on.  there are SO MANY options, i have no idea where and how to start.  the combination of settings are so many that it's counter productive to use trial and error.

the 485 board has jumpers, the computer has options for the 485, the six devices have jumpers & menu options, and dasylab has even more options on the RS-232 module settings; this is not plug-n-play as far as i am concerned

to fully understand what i have in hand, you would have to take a peak at the above links.  any suggestions?

thanks-tons, kiko

[CJ_Butler__DASYLab_Pro]

Looking at the device manuals, you want to configure each device for a different address.

That way they can be uniquely addressed on one RS485 port (comm. port).

I think that is the address described on p. 36 of the manual.

The manual talks about its own software, but does not describe the ASCII command language. So, I'm not able to help more.

No... the RS232/Serial functions of DASYLab are not plug and play. We have no drivers, nor have I ever worked with this device before.

[CJ_Butler__DASYLab_Pro]

I just found this manual,

http://www.transducertechniques.com/pdf/dpm3t.pdf

It says this on page 5

Jumpers d & f are installed for full duplex operation and jumper c & e are installed for 1/2 duplex
operation. Shipped with jumpers d and f installed. It is necessary to set up each DPM-3 on
the bus with a different address from 1 to 31. To command a particular DPM-3, its address is
used in conjunction with the command and only that meter responds.

And on page 6

Addressing of the DPM-3's can be done from the front panel using Menu item “Ser 2”, XXXXX.

[Kiko-of-Brasil]

CJ:

i feel pretty confortable with what i had setup on the DPM-3s.  however, i still have questions:

SEr2 on the DPM-3s (page 15):

line feed or not?

continuous data output or with ascii command?

SEr3:

special start and/or stop characters?

normal RTS or single-transmission?

termination characters or not?

parity?

now on the RS-485 board:

page 03...

JP1 jumper:

RTS or auto?

echo or not?

loop or not?

and what do i do in the 232 module in dasylab?  there are so many different things you can mess with...

data request?

format?

string?

reset, start, stop commands?  data request necessary?

how does all this tie in with the six different addresses of the DPM-3s? 

thanks, kiko