"Brooke Clarke" <[EMAIL PROTECTED]> wrote: >I'm writing an application where I need to be able to bit bang serial >port output lines and check the status of serial port input lines in LV 5.1. > >In the vi.lib\instr\_sersup.llb folder there is the serial line >control.vi and it uses two sub VIs to allow controlling the DTR and RTS >lines by using the "open serial driver.vi which can be opened and >figured out plus the Device Control/Status.vi which is a yellow vi and >can not be opened. > >I have the feeling that with the proper inputs to Device >Control/Status.vi it would be possible to read the status of the serial >port input lines CTS and DCD. > >Does anyone have details on using the Device Control/Status.vi?
You must be using LabVIEW before 7.0. The new 7.0 serial VIs use VISA to control the serial port and VISA coincidentially allows you to controll all those handshake lines over properties of a VISA resource. The Device Control/Status node is not a VI but a built in LabVIEW node which is basically obsolute in LabVIEW 7.0. It was a direct interface to the Macintosh Device Manager interface together with Device Open, Device Read and Device Write nodes. You could theoretically control any device driver under Mac OS with these nodes directly, altough doing so could get a very tedious exercise, as the interface was rather low level compared to the rest of the LabVIEW functionality. Under Windows NI created a Macintosh Device Driver emulation layer for the serial port, which was located in the omnious serpdrv file. No other device emulation files where ever released. The io control codes into the serpdrv file are not public and I actually doubt there are any others, besides of the ones available in the _sersup.llb file, although this driver evolved over time having no real additional control options in LabVIEW 3 up to allowing some handshake control in LabVIEW 5. Don't bother about this interface at all. It's not worth the hassle, will most probably go away in LabVIEW 8 or 9 and VISA offers you a more complete control of serial port aspects in a much more platform independant way. Rolf Kalbermatter CIT Engineering Nederland BV tel: +31 (070) 415 9190 Treubstraat 7H fax: +31 (070) 415 9191 2288 EG Rijswijk http://www.citengineering.com Netherlands mailto:[EMAIL PROTECTED]
