Re: [CAD_CAM_EDM_DRO] hydrapath 3 data transmission ???

Ron,

No experience with this particular system in general, but I just spent a
couple of days interfacing some other instruments to PCs via RS-232 ports.

I'd start by inserting a LED Board RS232 tester between the PC and the
CNC. See which channels are powered with the tester first connected to
the CNC and then to the PC. For communication to be successful, one
device has to be a DTE and the other a DCE, which is a fancy way of
saying that each system has to be talking on the right wires (and each
device has a different set of wires!). If you see that Transmit Data
data (Pin 2 on the DB 25 version) is being powered by both the PC and
the CNC, then that means that both devices are trying to send on the
same wires, and that won't work, so you will have to insert a Null modem
adapter between the PC and CNC. A null modem is a passive device that
swaps the transmit and receive lines around so two identical devices can
communicate. You can find null modem circuits with a Google search.

If you have the circuit set up so that both the transmit and receive
lines and their corresponding control lines are working, then check the
DTR signal on pin 20 That signal has been a frequent source of devices
failing to communicate. You may need to pull it to an active level by
jumpering it to one of the other control signals (usually pins 4, 5, or
6).

With the LED tester in place, you should be able to see activity on the
transmit data (2) or receive data (3) pin when you transmit from the
PC. At least you will know that data is going out at that point. If
there is no response from the CNC, then that is a problem beyond what I
can help you with.

HTH,,
Dave



rogersmach wrote:

> Sorry for the OT, does anyone have experience with transmitting data
> from a PC through an RS232 serial port and a hydrapath 3 cnc
> controller.
>
> Have one and can't get it to receive from the PC. Tried every setting
> we could. Confused about how to set the controller to accept data. Is
> the cable used standard or special. Any help with this will be greatly
> appreciated.
>
> Thanks, Ron