Running into memory issues Mitsubishi M-V60C - Meldas 300 Controller

[Josh Lehman]

Hello Everyone,

Just wanted to say right off the bat that this forum is great so many answers to different questions. Ive looked through some threads and did not come across anything like what I am going to ask. Maybe there are and I was just looking in the wrong place, anyways any help would be greatly appreciated.

I work in a custom fabrication shop where we have a Mitsubishi M-V60C 3 Axis Mill which is coupled to a Meldas 300 Series controller. The mill is connected to a pc via RS232C and communications between the two work flawlessly.

This is where the problem begins - Im not exactly sure how much memory these controllers have, buts im willing to bet its not alot in todays standards. I can fill up the memory very quick with a simple program from Mastercam 8 and wont even try Mastercam X until I get this figured out. I would love to create some really nice pieces, but have been limited to tiny programs up until this point.

At one time years ago my boss hired a guy to come and try to fix this issue. They managed to get the machine to run in tape mode while streaming the NC program from the computer via RS232C. The only problem was that the machine would run line by line, pausing between each line for a second or so.

I would like to learn how to setup this connection again and fully document it this time. I would also like to get the mill running continuously (not block by block) while using tape mode. If anybody can offer any help with this it would be much appreciated. Thanks.

Josh

[Josh Lehman]

I guess another option would be to upgrade the memory if thats possible, if anyone has insight on this as well please share.

Josh

[Caprirs]

Most likely, your machine will have 32K or 64K of memory. Usually, this is plenty if you are doing conventional 2.5 axis work. As soon as you do some 3D surfacing, you'll run out of room in a hurry. At that point, you will have to DNC/dripfeed programs to the machine.

I have two Dynamechtronics mills with the Mits M3 controls. I have successfully used Windows Hyperterminal, a 9-pin to 25-pin serial cable with a null modem adapter to do basic transfers to and from the machine memory but have not been able to use it for DNC/dripfeed. I listed off how I setup the machine and Hyperterminal here.

To be able to DNC, I am using software from andycarter (he posts on these forums). His web site is www.iworkshop.co.uk I also use isolators from Gordon Roberts (gar on the forums). Gordon's isolators prevent damage to the PC and control. Andrew's software is easy to use and works well.

[Josh Lehman]

Well I managed to get the machine partially working in DNC mode yesterday. By partially I mean that it was only taking part of the NC code, sometimes it was from the start of the NC file and at other times it was from the middle of the file. The machine also started to give me "E20 over run error", im not sure what this means. Now it will not accept any NC files from the PC in either memory mode OR tape mode, the prgram I am trying to load comes up on the controller but it has zero charachters its just blank. Its like the E20 error is stopping the communication between PC and controller.

My settings for communication are:

Baud Rate - 4800
data bits - 7
parity even
stop bits 2
Xon/Xoff

Does anyone know whats happening here? Again any help is greatly appreciated. Thanks

[Caprirs]

Check to make sure your FIFO buffers disabled on the PC. You access the settings in Control Panel -> System -> Hardware tab -> Device Manager. Find your COM ports and double click the one you're communicating with. Click the tab for Port Settings then Advanced. Uncheck the FIFO buffers. Having this turned on can cause problems with RS232 transfer, especially DNC.

[Josh Lehman]

Thanks Caprirs,

Im going to try the FIFO thing today and see what happens. Ill post the results.

[Josh Lehman]

Well I managed to get the machine working in DNC/dripfeed mode. Ran it all day yesterday tesing tool changes and trying new programs ive made in Mastercam X.

It was really tricky figuring out the right routine. We managed to get it working on monday, but when we tried to run a second program it wouldnt work. Just kept continuously streaming data until the controller memory was full. Well yesterday I figured it out, the routine is as follows:

--> Put mill in tape mode
--> Go to Input page on controller, then TAPE #(1) DATA(1111) then hit input (be sure this program number (e.g. 1111) matches the program number that is in the NC file you are going to run)
-->Open Surfcam DNC, can be found in surfcam directory in windows start menu.
-->Download NC file
-->Click "send" to Mill
-->File will start streaming uninterrupted. Hit Reset on milling machine, at this point file transfer has stopped in surfcam DNC. On the mill you should see “E07 RESET END”. In surfcam DNC you should read “waiting for XON signal”.
-->Hit reset in Surfcam DNC.
-->On the controller, delete the partial program that was just uploaded to mill.
--> Go to Input page on controller, then TAPE #(1) DATA(1111) then hit input (be sure this program number (e.g. 1111) matches the program number that is in the NC file you are going to run)
-->In SurfcamDNC hit transmit file button, it will stop and say “waiting for XON signal”.
-->You can now hit run button on mill and program should start.

I am using Surfcam DNC (we already had this installed) for the transfer. I will also mention that I did install a demo version of predator DNC and NCplot on the pc used for transfer. Not sure if the installation of those programs modified a setting in windows or something.

Thanks Caprirs and to everyone else here at cnczone.com for helping fix this problem. Ill have to post some pics of some of the stuff we are going to make on this machine.

Josh

[CNC Viking]

Originally Posted by Josh Lehman --> Put mill in tape mode --> Go to Input page on controller, then TAPE #(1) DATA(1111) then hit input (be sure this program number (e.g. 1111) matches the program number that is in the NC file you are going to run) -->Open Surfcam DNC, can be found in surfcam directory in windows start menu. -->Download NC file -->Click "send" to Mill -->File will start streaming uninterrupted. Hit Reset on milling machine, at this point file transfer has stopped in surfcam DNC. On the mill you should see “E07 RESET END”. In surfcam DNC you should read “waiting for XON signal”. -->Hit reset in Surfcam DNC. -->On the controller, delete the partial program that was just uploaded to mill. --> Go to Input page on controller, then TAPE #(1) DATA(1111) then hit input (be sure this program number (e.g. 1111) matches the program number that is in the NC file you are going to run) -->In SurfcamDNC hit transmit file button, it will stop and say “waiting for XON signal”. -->You can now hit run button on mill and program should start. Josh

I don't understand any of the RESET steps you are doing.
My CNC has a Meldas 520 AMR and set up for DC-codes.

These are my steps:

I start with opening my DNC software in the PC and then open the desired program O1234

1. Hit SEND to CNC in the DNC software in PC. THe DNC answers "Waiting for DC code".

2. Go to the CNC and select TAPE mode, hit DIAGN IN/OUT. Then hit soft button under the screen for INPUT.

3. Write #(1) DATA(1234) and hit INPUT/CALC.

4. Hit CYCLE START and the CNC starts running the program immediately.

When the CNC has completed the program, I can run it again just by repeating steps 1,3 & 4 again.
Just my $0.02

Now, I also have some memory related questions to anyone that knows:

1. Which buffer memory is used in the Meldas 520 when it is in the TAPE mode? I have the following memories. Believe it or not, my controler calls it "EXPANDED MEMORY". I don't dare to think what the standard package is like, lol.

QX424A=1MB SRAM on MBUS
QX635A=2MB ROM (External Casette memory) on CBUS1
QX812A=256KB ROM (External Casette memory) on CBUS2

2. I have not tried to DNC anything larger than a few KB yet, but want to see what happens when it reaches the buffer limit.

I want to see that it stops properly before buffer overrun and that it starts to fill up again before emptied "seamlessly" without any hick-ups etc.

Is there any good, and big enough, test program(s) that one could download and test cutting air with.

Is there a way to "consume" such a program quicker so I dont have to wait hours for the result? Maybe change the feedrate etc?

/Peter

[Josh Lehman]

CNC Viking,

"1. Hit SEND to CNC in the DNC software in PC. THe DNC answers "Waiting for DC code"."

When I would try youre step #1 on my machine, the DNC software just keeps sending. Once or twice it would stop right away and display a "waiting for"
message, but 99% of the time it would just keep going, even with the controller in tape mode. Not sure why I have to go through the reset routine to get it to work. Does anyone else know why?

As for your memory question, im really not sure. Hopefully someone else will see this thread and reply to your question.

We just made up a program in mastercam that was about 2MB and ran it on a chunk of wood. We were able to crank up the feedrate so the program would run faster.

[CNC Viking]

Josh,

Have you checked your stop bit settings? If the DNC doesn't see the XOFF signal quick enough, it will overrun the buffer. Some people even add delays and what not.

FYI read these other threads:
http://www.cnczone.com/forums/showthread.php?t=20283
http://www.cnczone.com/forums/showthread.php?t=49089


Re. The testing with a large program. I am not there yet. I will soon get a CAM program, but want to test this now. So any working 2MB-ish 3-axis program to test with would be appreciated.

/Peter

[Caprirs]

Josh,

CNC Viking's method is similar to my procedure with the M3 controls and Andy Carter's DNC software.

1. Open the file on the PC using the DNC software. Start sending the file.
2. On the mill, select TAPE, enter the program number and TAPE(1) and press INPUT. With the DNC software active on the PC, the mill should see the RS232 port as enabled and find the first line of the program.
3. Press CYCLE START on the mill.

It sounds like either the stop bits are not matched or there's something about the wiring between CNC and PC. Remember that the Mitsubishi parameter for stop bits is:
1:1 bit
2:1.5 bits
3:2 bits

[CNC Viking]

I never see any other recommendations than param. 3=2 stop bits. Thats what I use too.

But I have not tested large programs yet.