[bryanpflum]

Have 2 comet cnc mills both have mits meldas 520 controls. Having a problem with 1 machine as soon as i hit the input button i get the E08 error even tried switching rs232 cables . Have checked parameters also .Any help would be greatly appreciated .

[Jonsmachine]

I've spent the past two days reading countless pages filled recommendations and information on how to successfully connect a PC to the Meldas 500 series controller. I tried about 4 different cable configurations and MANY different parameters settings.

At one point I did get that E08 error and it was when my parameters were not cooperating. According to the manual: "E08: PHYSICAL ERR - The settings of an input/output parameter in the NC or the input/output unit is incorrect." So you're close!

I am going to post all of my parameters and cable configurations in hopes of giving back to the community that has helped me. (the search function is a powerful tool!) Take this information lightly, as you may be in a different situation. Document your current parameters before you go and change them to the ones I provide.

First off, here are my IN/OUT parameters set in the Meldas 500 Series controller.



^^ I am using port (1) and device (0) for my transferring in and out.



^^ Here are my parameters my port/device. "De-coded" machine parameters:

2. Baud Rate : 1 (9600 bps)
3. Stop Bit: 3 (2 bit)
4. Parity Effective: 0 (No Parity bit during input/output)
5. Even Parity: 0 (Odd Parity)
6. Chr. Length: 3 (8 bit)
11. Handshake: 1 (RTS/CTS) for SOFTWARE handshake. May be different if you wire for hardware shaking.

(See below for my computer parameters.)





This is my current computer sending and receiving setup:



So YES I do have two different data bits. My NC is configured for 8 and my computer is configured for 7. AND the NC parity is disabled while my computer is EVEN. Why does it work? No clue, but it does! My end result coincides with everything I have read on this controller. Things are screwy. Ok, now onto my cable configuration.

I ran into many complicated cable configurations when searching for help on this subject. My end WORKING cable design came out pretty simple.

This is the wiring that worked with my parameters. I really hope this information helps you and anyone else that searches for it.

[Jonsmachine]

Duplicate post.

[CNC Viking]

Hi,

This part is OK.



Then the following cable layout and settings work great with my MELDAS 520AM in my Feeler FV-800VMC. Cable length is not important as long as you keep the total cable length from PC's COM-port to CPU-module in CNC below 15m.



Good luck with your drip feeding!

[Jonsmachine]

Thank you very much! Maybe I will try that configuration tomorrow morning.

[CNC Viking]

You are welcome Jonsmachine,

Some more comments about your original setup though:

Parameter #2, 1=correct for 9 600 Baud. Not many know that value 0=19 200 Baud though.
Parameter #11, RTS / CTS is Hardware handshake, not software. DC Code and XON / XOFF is software handshake.



I am not sure if it makes any difference, but I always have parameter #2, CR output set to value 1=On, no matter if handshake is hardware or software.


So, I only have different settings in screen 8. 2/5 for Hardware vs Software settings:

Hardware settings:
Parameter #11=value 1 for RTS / CTS (Hardware Handshake)
Parameter #12=value 0 for No DC Code Parity

Software settings:
Parameter #11=value 3 for DC Code
Parameter #12=value 1 for DC even Parity added

ALL other CNC Parameters are left as they are unless I change the Baudrate value (Parameter #1) of course.

DNC program settings:
If you mean to use RTS / CTS (Hardware Handshake), RTS / CTS should be checked here.


Cable configuration:
1. I think you got it wrong on the Computer side. Pin #7 (RTS) should be pin #5(Signal ground).

2. Since MELDAS 520 work so good with real RTS / CTS signals, why fake it by jumpering pins #4 and #5 on the CNC side? Make the real PC-to-CNC connections instead. See diagram in my last post.

3. Since my CNC's 25-pin receptacle does not have any wire connected to pin #8 (look behind the the panel on your CNC control), I do not jumper pin #8 to pins #6 & #20.

4. Note, I also have a jumper wire between pins #4 & #6 on the PC (Computer) side.

5. I have found that my cable configuration works with all handshake settings that I have tried so far (RTS / CTS, DC Code, XON / XOFF).

[Jonsmachine]

Once again CNC Viking, THANK YOU! And you're right, I did not know about the 19,200 Baud rate available. The manual does not mention this value as an option.

I am trying this configuration right now. I will report back with my results. Your time and effort is much appreciated.

EDIT: Everything works flawlessly, even the 19 200 baud rate. Thanks again.

[Jonsmachine]

Maybe I posted too soon. Although I can send programs OK, I am unable to send a program back to the PC. The output procedure will not start at the controller, just stands still. I will report back if I figure it out.

[CNC Viking]

Have you pressed "Receive" at DNC program first? Then program use to say: "Waiting for CNC". Then go to CNC control > select DIAGN. IN/OUT> Output > select program(s)>press INPUT CALC (green button). As soon as you press this button, the programs shall immediately be transferred to the PC.

Have you checked cable continuity? Not just between the PC and RS232 receptacle at the control panel, but also any intermediate cable from there to the CPU-module!