A bit of dripfeeding help please

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bishbosh
Posts: 19
Joined: Tue 15 Apr , 2014 8:42 am
Hardware/Software: TRIAC FANUC OM-C
Serial TR29080 A
Manufactured Oct 1990
Control Serial 9112024

A bit of dripfeeding help please

Post by bishbosh » Sun 28 Sep , 2014 14:21 pm

OK, so to my surprise I have managed to get my Windows 7 laptop to talk to my 1990 FANUC Triac.

I am using a USB to RS232 board like this:http://www.ebay.co.uk/itm/260836648666 and a 9 way to 25 way RS232 lead made up to the specification quoted elsewhere on this site.

I put the machine in DNC mode using M29 and pressing cycle start. A second press of cycle start then starts the LSK light blinking - all good so far.

On the laptop I am using the free version of One CNC's NC-Link.

When I send code from the laptop the mill starts up and follows approximately the first 3 lines of code perfectly. I have noticed that very soon after I start transmitting that the BUF light comes on on the screen.

The software also pauses during the transmission after about 6 lines of code have been sent. When I cancel the transmission, the mill then executes the next three lines (i.e. all that has been sent)

This would appear to be a buffer issue but how do I overcome it? There is no FIFO option in Device manager for the port I am using so cannot find a way to disable it (which is apparently one potential solution?)

Any clues folks?

Thanks,

Charlie.

Taylon
CNC Apprentice
CNC Apprentice
Posts: 48
Joined: Fri 05 Apr , 2013 0:14 am
Hardware/Software: Standard PC using Firefox Browser.
Denford Viceroy TDS/PCS version 2 Metric Lathe
Location: Staffordshire, UK

Re: A bit of dripfeeding help please

Post by Taylon » Thu 11 Dec , 2014 21:55 pm

Hello,

Have you fixed your buffer issue? There is 2 ways to control the buffering on a serial port;

1) By hardware - RTS and CTS signals and the serial cable has to have those lines connected correctly at both ends of the cable with your computer and controller set to use this method of buffer control.

2) By software - using the Xon and Xoff signals that control the data flow to and from the buffer by your transfer program.

Depending on how your machine controller is configured will determine whether you use hardware or software buffer control but both ends of the cable have to be configured to use the same buffer control method with the same baud, parity, and stop bits set.

Kindest regards, John R.

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