[fm.ind]

Hi everyone,
I sometimes run long programs using DNC on my Fadal VMC15 for an hour or more. The communication link seems to fail randomly, 1-4 times per hour. The communication link is a via a serial cable (I think it's shielded) approx 80 ft. long.
When it does fail, the last line of code that was transferred stays on the screen, and the machine just stands there, spindle and coolant running.
This failure occurs using any baud rate from 9600-38000.

What is causing this problem?

-Thanks

[HuFlungDung]

Just a wild guess, but I'd be looking at the power settings for your PC. You want to turn off absolutely everything that wants to put the computer into screensaver mode, or power down the hard disks. The PC needs to stay totally awake for the entire duration of the transfer.

[fm.ind]

Ha! you insult me!

The computer does not go into sleep mode, turn on screen saver, or any other action that might cause the failure, anyone else have a problem like this?

Cheers ))

[HuFlungDung]

Not meant to be an insult

Check your PC task manager for any other processes that might be intermittent, like any update seeking functions, whether it be for antivirus or windows update.

Is the line of code that it stops at syntactically correct? Or is there a bad character reported? 80 feet is a fairly long cable, I'd go with a much shorter one with a PC near the machine and see what happens.

[fm.ind]

The code is good. I can't see any reason why the computer would interrupt the process, or even that it does.

I can run the same program multiple times over an hour or so, but it's guaranteed to stop, but never on the same line of code.

[Paul_S]

A baud rate of 4800 will work. 9600 baud with a shielded cable of 80 feet can be flaky just sending and receiving files. I've had the same problem. So I use 4800 baud. We do not use the DNC any more. We have machines with enough memory.

If you need to use the higher baud rate, use a PC right next to the machine with a 6 foot cable. I've used the 9600 baud or higher that way doing DNC.

[Waynno]

I have an 94 Fadal VMC 40, 4800 baud max on a 40 foot cable

9600 baud, errors are common here, Have had good luck running DNC at 4800

If 4800 is not keeping up with what you are doing, maybe relocate computer (Laptop)
closer to machine and use shorter cable to get faster drip feed

[DareBee]

I have no issues with DNC on my 94.
12+ hours at 38K baud.
Cable is about 20' and the other than screen saver/hibernate being turned off, the laptop does whatever it wants in the background (I assume)