[barchdesigns]

Neither of my Fanuc 6M Vertical CNC machines had a way to truly "drip feed" through the 25 pin serial port. The serial port was only used for transferring a program from an external computer into the NC's memory, and not for drip feeding commands as it is running.

It seemed the only way to run a very large program was through the old Paper Reel to Reel Tapes. After looking into the electronics of how the tape drive worked (and determining I had a bad head reader) I decided to find a way to make a Tape Drive Emulator so that I could use this machine with very large programs. I made am interface board that has an Arduino MEGA with an attached shield with a Network Port on one end, and a Multipin Ribbon Cable Receptacle on the other end. It has been in service daily for over 2 years now without an issue. It has been put to the test and the only limitation is the size of the micro SD card. With gigabytes to play with I didn't have any space limitations anymore.

Has this been a problem for anyone else? I'm trying to determine if I should document and share the information of how I solved this problem.


Barch Designs
877-201-9771

[aarggh]

This is absolutely of no use to me, but this kind of info would be priceless to someone struggling with a similar issue, so yes, please document it and post it as I'm positive others will find it useful at some point!

Better to have it and not need it than need it and not have it I reckon.

cheers, Ian

[gfacer2]

I agree, sounds like an awesome upgrade. Just the sort of thing that makes cnczone a great place.

Sent from my LG-D852 using Tapatalk

[barchdesigns]

Let me get clearer, Is anyone actually looking to put a Behind the Tape Reader (BTR) on a Fanuc 6 control, or is it a theoretical problem that could exist? I'm thinking of having a small run of professional circuit boards made to replace my prototypes, and I'm wondering if anyone would pay money for this Interface Board solution? I have to make about 10 of them to fill the minimum PCB order. If it really isn't an actual problem I'll just leave my prototypes in the machines as-is, but...

I would love to take the project further to include features such as

* Display % finished
* Current line output
* Control mid program starts

through a web app interface (Control it with your cell phone). I can only justify taking the time to work on the project though if it will directly help someone else.

[gfacer2]

Ahh, well I'm not. I just thought a post of the arduino sketch and a quick diagram or description of the connections would be invaluable to anyone else that may stumble upon this in the future.

I would think you could add all those features in the sketch relatively easily (except the last one maybe).

Sent from my LG-D852 using Tapatalk

[ovaiswahid]

Can you please share the arduino sketch with schematic so I can use it to DNC my fanuc 6M ?

[ovaiswahid]

CAN we increase the baud rate between this BTR and the 6M? i have a BTR whose baud rate is fixed....the machine halts in between very small straight lines ...while simultaneously moving x , y and z axes..

[memoryman]

BTRs have been around since the '80s. The Baudrate is between 150 and 600. Doubtful that there is much demand for yet another BTR.

[barchdesigns]

My feeling from this thread it most people think it may be useful for someone else, but I haven't seen a need for it by anyone personally (as memoryman said, yet another BTR). On my particular 6M machines the baud rates are selectable up to 1,200. I've pushed it a bit beyond that manually, but any faster and it starts skipping characters. The electronics just don't go faster than that on a 6M. I also get the small pauses when running a program with many lines of short distance. Best thing I have done with the Arduino is parse each line to remove any unneeded characters before it even gets sent to the machine (Line numbers, comments, etc). Second best thing is optimize your toolpath to use arcs instead of many small straight lines (Some CAD programs are notorious for generating arcs as many small lines)

The biggest problem that was solved for me was running a 2 Million Byte file on a machine with only 32 Thousand bytes of memory. I can run the whole program from start to finish through the Arduino BTR. Where as before I would have to break up the program into many small pieces and send it over to run each piece at a time. I have eliminated the time it took to transfer the program from a computer to the Fanuc memory each time, and I don't have to be there to keep changing to the next "chunk" every hour. I can now start my machine and walk away for 8-12 hours.

As a home shop I needed to find a cheaper solution than a expensive industrial BTR (which I know are just simple electronics and you're paying for the convenience of someone else building it for you). The Arduino and some 1/8 watt resistors are basically all it took to build the prototype.

Barch Designs
877-201-9771

[ovaiswahid]

I am in need of this arduino based BTR for replacing my old BTR running at 300 baudrate...unfortunately there is no jumper at all or any other switch to increase the BTR...
I do appreciate your efforts in building it so..would be grateful if you share the arduino sketch and the schematic

[ovaiswahid]

[email protected]

[ppaing126]

could you share your work...?
I need to build something alike to drip feed to my Fanuc 6M

[agering]

I used the device IIN-DNC from STRAUS company which safely works before 38400 bits/sec baudrate. Reach such speed allows the double data buffering and built in Windows kernel the DNC software. This BTR device has an interfaces for RS232 and PTR+PUNCH connections, supports the all CNC protocols.
Manuals for it here:
IinDoc
Sorry, that much from it in russian.

[memoryman]

the btr baud rate is limited to the 6 control's tape speed; I think the maybe 600 Baud.

[ovaiswahid]

does any body has details of 50 pinout on the fanuc main board...and the timing diagram of this port while it receives data from tape ..which pdf manual should i search?

[agering]

the btr baud rate is limited to the 6 control's tape speed; I think the maybe 600 Baud.

PTR interface in 2.5~3 times slowly than RS232C. For increase the baudrate it is necessary remake the interface PTR (CAT). Need to do that could read symbols under short pulse SP (sprocket). The Second way, add the patch to software for activation Drip Feed to RS232.

[ovaiswahid]

can any body share or guide about the 50 pinout of the fanuc main board which receives data from the tape reader.....also i need the timing chart of its communication

[barchdesigns]

Hi, We didn't use a protocol. We literally just turned the 9th pin high or low by a delay function. The Fanuc tape reading head just turns 8 wires high or low and the 9th wire is like a firing pin. The Fanuc reads the 8 wire states when the 9th pin is active. I believe we found around 1 millisecond on and off worked about as fast as Fanuc would read it.

The arduino sketch just reads a text file character by character and then looks up the cross reference table to see what state the 8 pins should be in for that character. The arduino sets the state of those 8 pins and then makes the 9th pin active (I believe it was active low) for the delay time (just long enough for it to be read by the fanuc transistors.) To eliminate wasted time by sending non-movement characters such as comments and line numbers we also added a preview function to strip those characters before sending anything to the fanuc.

[ppaing126]

bar, thank you for the information. Yes I saw the 8 bit likely driving lines, not aware of the 9th pin. Also, good to know you use a lookup table. I saw the characters table on the manual.
I think I can do it now with your information and the manual.

I will start doing some tests.

[memoryman]

There are several btrs on the market and have been for decades. I have been involved in two designs. The 9th signal is the sprocket signal. A friend at another company told me 20 years ago that they could read ~600 chars/sec.