serial read and write

[sekhon]

hiiiiiiiii ......... i have to run 3 hardware simultaneously......... with the help of visa i am able to implement programe for one hardware . By using rs232  interfacing is done between pc and hardware..... now plz suggest me how i am able to run 3 hardware.......  by using some extention on com it become possible or i have to deign some another hardware for that........plz help me and thanks

[xdaf]

RS-232 is intended for point-to-point communications -> unless your PC has 3 serial ports (which I doubt) you should choose a different BUS (such as GPIB or ethernet).

Regards

[JB]

...or use a RS232 interface with several ports. For example from NI. 

[Curt_C]

You could also use 9 pin rs232 to USB converters.

Curt