How do I send a string output from a DAQ Board (NI- USB 6259) using labview? I want to send commands such as " CELL 0" or "READ" to a potentiostat device using labview.
Thanks
+3
A:
The 6259 doesn't do string output. It's a data acquisition board that's intended for reading/sourcing analog voltages or sending/receiving individual digital signals. It's not a communications device.
If you're really trying to send strings to this device, you probably need something more like an RS-232 or GPIB connection.
eaolson
2010-05-11 03:35:40
+1
A:
As eaolson said a DAQ is not intended to control devices. However it is an interesting project to enter the guts of the communication protocol. Doing it with a DAQ would require to:
- Identify the protocol (GPIB or RS-232)
- Make your cable from the DAQ output connector
- For each command, generate the waveform in LabVIEW, by using the letters' ASCII code, stop bits, etc. This is the funniest part (INMHO, but I understand it's not everybody!)
- Send it (using DAQ analog write VIs, you should find many examples for this)
- The oscilloscope will be your best friend
CharlesB
2010-05-11 06:42:11
Sounds fun (seriously!) but, just for reference, a USB to RS232 converter will set you back about $15US. USB to GPIB, about $150-$250.
Underflow
2010-05-11 14:34:43
thanks for the idea!
hkf
2010-05-11 16:11:17
How interesting this sounds I would try this with the digital output, so I don't have to think about the timing.What is the signal level of GPIB? RS-232 exceeds the standard 5 V. for a 6251 board (it's 10 V).
Ton
2010-05-11 17:13:56
RS232 levels are all over the place: http://en.wikipedia.org/wiki/RS-232#Voltage_levels. The joys of old standards...
Underflow
2010-05-11 18:56:00