DMM MAS345 via RS232 serial comunication

[yiomada]

i have a problem almost like u,and i want to know if there is someone who can help me.I want to send data from a DMM MAS-345 via Rs232(my data settings in labview are baud rate=600,data bits=7,parity=none,stop bits=2,flow control=none,delay before read=10000ms) ,and i don't know why does it showes an error when i try to run the application(error -1073807202).I use like example VISA configure serial port,and i don't know if is wrong!!!I will appreciate if someone can help me.

[Coq_Rouge]

Here is some help for you 

MAS345
data format: 7n2 at 600 baud (7 bits, no parity, 2 stop bits).
Control lines:
   DTR and RTS lines are used to power the TX line: RTS is clear
   for -12 supply; DTR is set for +12 supply. Data transmission is
   solicited sending whatever character to the RX line.
Data string format:
   MAS-345 sends a 14 bytes string with:
         <mode>< ><sign><value>< ><units><return>
   <mode>:  two bytes with the oerating mode: DC, AC, OH, CA, TE ...
   <sign>:  one byte with - or space
   <value>: five bytes with four digits and one decimal dot.
   <units>: four bytes with the units: mV, A, kOhm, nF ...
   <return>: '\r'
   One space is inserted between <mode> and <sign>, one between
   <value> and <units>.
   The data string (without the '\r') is sent to the output device.
The next question is of course How Can I Control the DTR and RTS Serial Lines in LabVIEW? It is easy take a look here

http://digital.ni.com/public.nsf/allkb/1ECEFAA7AD52994986256966005356EA

Good luck

[yiomada]

Thanks alot,i will try it and see if it would work....i'm not so good in labview because i'm a beginer and i hope this would not be an unsolved problem because is verry important for me!!!

[Coq_Rouge]

Also see here

http://forums.lavag.org/Multimeter-serial-communication-t5200.html&mode=threaded&pid=21065

[treii28]

Question on the DTR line. I am interested in trying to drop a bluetooth module inside of my meter to see if I can get it to connect to the PC wirelessly, but the module has no DTR and only an RTS at Uart voltage levels.

I'm wondering what, if anything, I need to do in regards to the DTR and RTS connections? If it's being used to power the tx, can I just shunt power back into it with a resistor of some sort?

[KyleP]

Hi treii28,

If you are looking to output a voltage from the DTR and RTS lines on your MAS345, you can refer to this KnowledgeBase article for more information. 

Cheers,

[treii28]

I'm not sure what I need to do. All I know is I have no computers with an RS-232. I've tried connecting it to both linux, windows 7 and windows xp virtual machine using both a FTDI and a prolifix based USB-to-RS232 converter with no luck on any of my attempts. I figured trying the bluetooth option might be my next best shot at getting this thing to talk to something. I have a basic bluetooth slave module that claims to have a RTS and CTS wire but nothing for DTR/DTS. It's uart voltages but I have a converter coming as well as a few schematics lest I wish to build one myself.

I just want it to work and the instructions with this thing are very vague. I've learned it has an RTS line and the DTR line, and saw at least one posting claiming it needed a high at DTR to work properly - what that means, is beyond me. I don't know if the software in the PC is expecting to see it or if the device expects to see it and I am not sure which is even behaving as the DCE. I'd assume the meter is sending and the computer is receiving for the most part but beyond that is just guessing.

[KyleP]

Hi treii28,

What sort of trouble are you having with your USB-RS232 converter? I'm assuming you mean a product such as this. How come you are using a virtual machine? It would probably be best to first establish a connection to the computer's actual OS.

Cheers,

[treii28]

The software was written about 8-10 years ago and thus will only install properly on windows 95 through windows XP. I was playing with the virtual machine so it would be in a similar environment to what it expects, but then just had trouble getting the RS232 connection to work.
I was able to copy the program folder out and it ran under regular windows 7 but still was unable to get it to talk to the US-to-RS232 adapter I have. I just want to get the meter talking to the software but haven't seemed to have much luck.

[Dennis_Knutson]

So this 'software' is not LabVIEW? Any National Instrument products at all?