Can't seem to send a command via RS-232 to a Particle Counter

[Matt Ownby]

I have a Climate CI-500 particle counter. At the moment all I really asking for it to do is to turn it on, run for 6 minutes, and then turn off via it's serial port. It has the usuall 9600 baud, 8 data bits, 1 stop bit, no party, and DTR control. I've got to turn on and off via Hypertermial but nothing happens when I use LabVIEW 6.1. The device does send maybe about 5 lines or so every six seconds, but I'll try to get that later. I've set all parameter in Serial Config as constants.I don't have hyperterminal running at the same time. So, I'm at a complete loss as to why it doesn't work.

[Chris_Rake]

I've taken a look at your code, and have a couple of questions/comments. The commands "S" and "T" - are they the power commands? Do they have to be followed by a CR or LF? Also I noticed you have the flow control set to DTR/DSR. This is a little unusual but not unheard of. If the hardware is calling for "hardware flow control" chances are that you'll want to use RTS/CTS instead. Also, you can verify that VISA is sending the data by running NI Spy. If these commands work in hyperterm, I see no reason why they won't work in LV.

[Matt Ownby]

'S' is the start command and 'T' is the termination command. Commands are terminated with CR but I wasn't sure if I should type \n or just enter the CR. The ops mandual says that ouput drivers are tri state with DTR recieve line enabled. It also said that it was used for handshaking so I though that DTR/DSR was the right mode. It does mention CTS but together with DCD and DSR saying that 'they are held in the high state as the serial port is interrupt dirve and is always ready to receive'. The Serial Cofig seems to be set at xA = '\n' = LF But, if that is case, then what is CR?