Need Help!- Bridgeport eztrak dx 2

[markjab]

Hi guys, My name is Mark. Ive been machining for 28 yrs now. Twelve of those yrs have been spent on a Bridgeport eztrak dx 2 , purchased in 1996. My boss just bought me a new dell workstation -- 3ghz fast w/ 4 gb of ram which runs windows xp64 and mastercam x3. I have the correct .mmd -- .control and .pst files and am able to put a part program on a 3 1/2 floppy in .txt format and load the cnc w/ that. I am trying to connect the pc and cnc via rs232 cable. My baud rates -- parity -- data -- stop bits are all step up to match but I cannot seem to connect. I'm trying to transfer the files in the ASCII mode. I have been reading on this forum about the ezlink software. Does anybody know if this will help me or if this connection is even possible? Any input would be greatly appreciated. Mark

[wehrmeyer]

There are 2 more requirements for RS 232 serial communication to work. The first is DTE/DCE. The DTE machine transmits on pin #3 in the 9 pin connector on your communication cable. The DCE machine transmits on Pin 2. In order for communication to take place one machine must transmit on #3 and the other must transmit on #2. It is typical for a PC to transmit on #3. To see what pin the Bridgeport is using , using a digital voltmeter measure between pins 2 and 5 then 3 and 5. Pin #5 is signal ground and the the transmit will have some voltage like -8 vdc. The receive will have near 0 vdc. If the bridgeport and the pc are both transmitting on #3 then a null modem adaptor or a null modem cable will fix that. Either is available at Radio Shack.

The other setting is flow control. The choices are none, Xon Xoff, or hardware. The Bridgeport is expecting some condition to accept a message. None means that you can just send a message at anytime. This works well for short messages. X on X off is a software protocol where you send an X at the beginning of a message and an X at the end to mark the end of the message. Probably bridgeport uses hardware control which uses some of those other wires in your 9 pin cable to make the handshake between the two computers, all you need to do there is make sure the port is set to flow control "Hardware".

If that doesn't solve the problem you can build a sniffer to capture the communication between the computers for less than $20.00.

I was reading the post because was interested in an EZ Trak for producing short runs where I work. I work in the electronics industry and have used a manual machine to build fixtures. How is your experience with the EZ Trak machine . I have also looked at Centriod conversions.

[markjab]

Thanks for your help -- I will check the pins. I think that the eztrak would be a good machine for eletronic shop fixturing work. It's not a machine that's suited to making massive cuts but for fixturing or prototype work , it's easy to program and works well. One note: If the machine comes with a 3rd axis option make sure it is the kind that drives off the stop nut on the quill. There was an earlier version that used an arm which clamped on the lower part of the quill. This method did not work well and actually caused the quill to flex to the side resulting in inacurate work. Mark

[Gncc50]

Hi Mark,

I have noticed several posts on this forum and others requesting information for the rs232 connection for an EZtrak. I have used an EZtrak for several years and have never had the need to load a program via the rs232. I always thought that was one of the great features of the machine was the floppy drive and how easy it was to load programs.

Just curious why do you want to load your programs in this manner??

Pete

[markjab]

Hi Pete For smaller programs I can load w/ the floppy drive. In the past -- using earlier versions of mastercam we generated programs larger than a floppy could hold. It was a pain having to break them into parts and since the machine has a com port -- why not? Mark

[Gncc50]

The capacity of the floppy should allow you to run a fairly large program somewhere in the neighborhood of 50,000 - 60,000 lines. It would take your Eztrak several hours to run a program of that size. Are you drip feeding from the floppy so that you can utilize the full capacity of the floppy (1.44 meg)? if not, your programs would be limited to 256k the limit of the machines buffer.

The reason I ask, I have seen this asked several times before and many people aren't aware that you can drip feed from the floppy or the machines hard drive. You can also copy and paste programs together if you have exceeded the limit of the floppy.

I'm not trying to be sarcastic or give you a hard time. Just trying to help.

Pete

[markjab]

Hi Pete --- That could be my problem -- Could you spell out the procedure for drip feeding off a floppy? Also when you cut and paste a program together are you doing that in DOS? I'm not sure how to do that within the EZTrak software. Most of the time I program the machine directly on the controler in MDI mode and have limited experience w/ loading mastercam generated programs. Thanks alot for your help. Mark

[Gncc50]

Hi Mark,

Check out this thread. If you have any more questions on Drip feed let me know.

http://www.cnczone.com/forums/showthread.php?t=80418

To link two programs together.

First copy the entire contents of your floppy to the hard drive. Then put the remaining portion on another floppy and then paste it to the first program on your hard drive.

To copy and paste go to edit and hit 5 for copy a dialog box will pop up and ask from what lines you would like to copy. Then go to just before the program end line and hit the + key. See attached .jpgs

This is a pretty slow process and takes a long time. But it works. Once you get the Drip Feed figured out you will very seldom have to do this, if ever.

Try it, let me know how it works out.

Pete

[markjab]

Hi Pete That info is great -- It's amazing how much I didn't know about a machine I've been working on for so long, but the way I see it -- if you don't ask you'll never know. I work at SUNY at Stony Brook and have some of the computer guys in the dept. helping me w/ the cable. It's a huge help to know that if we can't get it to work, I have an alternate method of transferring files to the CNC. Your help is much appreciated. Mark

[Gncc50]

Mark,

I'm not sure, because I have never used the serial cable to transfer programs. But I think you will still have to go through the drip feed process that I described. The rs232 cable will only transfer your file to the hard drive. You will then have to drip feed it from there. You will still have the 256K limit. So I don't think there is any advantage to the cable method unless you are running files larger than the capacity of the floppy.

Glad I could help.

Pete

[Gncc50]

Mark,

I googled Suny at Stony Brook. They should certainly be able to help you out. Sounds like you have a great job.


Pete