Need Help!- File transfer problems

[DavidRASKL]

Hello All, I am new to the world of CNC stuff so please forgive me if this problem has an obvious answer.

I have an SCM Record1 router with a NUM720 controller connected via serial cable to my PC and am attempting to transfer files. I am using NUMs own NUMCOM software on the PC. When I transfer a file from the controller to the PC it arrives no problem, all the data is there, uncorrupted (even at high baud rates) except for the very last line of code (XOFF or % or EOR, I have tried all three) where there is only a small, strange looking square character which I have never seen before. When I transfer files from the PC to the controller I have a similar problem; the program arrives on screen perfectly except for the last line which doesent load and the controller reports error30 (plotter fault or DNC line fault). The controller then doesn't save the file.

I have checked my cable against the NUM supplied diagram and am sure I have wired it correctly, I have checked all the software settings and have tried them in many configurations but always get the same error.

On another issue, my controller is quite old and doesn't have the ability to DNC drip feed and only has 64k memory. Does anybody have any advice (apart from 'buy a new controller' :-) on what I can do to be able to run files larger than 64k?

Thanks in advance.

[angelw]

Originally Posted by DavidRASKL Hello All, I am new to the world of CNC stuff so please forgive me if this problem has an obvious answer. I have an SCM Record1 router with a NUM720 controller connected via serial cable to my PC and am attempting to transfer files. I am using NUMs own NUMCOM software on the PC. When I transfer a file from the controller to the PC it arrives no problem, all the data is there, uncorrupted (even at high baud rates) except for the very last line of code (XOFF or % or EOR, I have tried all three) where there is only a small, strange looking square character which I have never seen before. When I transfer files from the PC to the controller I have a similar problem; the program arrives on screen perfectly except for the last line which doesent load and the controller reports error30 (plotter fault or DNC line fault). The controller then doesn't save the file. I have checked my cable against the NUM supplied diagram and am sure I have wired it correctly, I have checked all the software settings and have tried them in many configurations but always get the same error. On another issue, my controller is quite old and doesn't have the ability to DNC drip feed and only has 64k memory. Does anybody have any advice (apart from 'buy a new controller' :-) on what I can do to be able to run files larger than 64k? Thanks in advance.

The small, strange looking square character you see can be one of a number of non-readable characters such as Null, DC2, DC4 and SUB to name just a few, they can all look the same when displayed.

When you say that you have used all of the following characters (XOFF or % or EOR) at the end of your file, do you mean that you're literally using those characters, or the the characters from the ASCII character set for these characters. Unless the software being used has a function to decode the literal string into an ASCII character they will be read as X O F F ect, and not the control character DC3 (XOFF)

When a comms system is set to use XON - XOFF handshaking, DC1 (XON) and DC3 (XOFF) are not literally sent and received as part of the text file being sent and received. These characters are interpreted at System level and you never get to see them in your program. Depending on the software, you may get to view them in the program if No Handshaking is used during the transfer. I do this under controlled conditions when debugging comms software for unusual controls when I need to know what control characters are being sent.

If you want to know what the character is, send a copy of one of your files containing this character by PM and I'll interpret the character for you. If its a control character, you may have to have comms software that is able to be set to react to this character.

Regards,

Bill

[DavidRASKL]

Hello Bill, thanks for your response. yes, I was actually typing in XOFF. I have determined through trial and error that the little square character is the XOFF command. Thanks for the hint. I am however still having the same problem. Sending files to the PC from the controller works fine but when sending from the PC to the controller the last line or 2 always fails to send and the controller still reports error30 (plotter or DNC link error). I Made a new cable incase it was the problem but I still have the same problem. What do you think I can try next, any suggestions?

[angelw]

Originally Posted by DavidRASKL Hello Bill, thanks for your response. yes, I was actually typing in XOFF. I have determined through trial and error that the little square character is the XOFF command. Thanks for the hint. I am however still having the same problem. Sending files to the PC from the controller works fine but when sending from the PC to the controller the last line or 2 always fails to send and the controller still reports error30 (plotter or DNC link error). I Made a new cable incase it was the problem but I still have the same problem. What do you think I can try next, any suggestions?

How did you determine that the character was DC3? As i explained in my last post, if the PC software is set to Xon Xoff handshaking (software handshaking) characters DC1 and DC3 will not be seen in the received text stream. These characters are interpreted at system level and the software routine that's capturing and displaying the incoming data on your PC monitor does not get to see these characters.

From the sounds of it, I would think that the control software is looking for a particular end character. Some comms software reads and processes data in chunks, that is, a certain number of characters have to arrive at the Input Buffer of the Uart before its processed. Others, and its the method I prefer, will react as soon as 1 character is there. Now this is mere speculation, but it could be that the last couple of lines do not contain enough characters to trigger the store and display routine of the control software and because there is no required End Of Record character to force the control to take whats there and finish, the control software times out, generates the error message and leaves the last two blocks behind.

Early Fagor controls required a particular control character sent as the first and last characters, without these the control would go into error. The control would start to receive data if the first required character was there, but, understandably, would not know if the last required character was there until no more data was coming its way.

Do you have the manuals for the control? If so, see if there is mention of any required control character at the end of the file.

Does your PC comms software have the functionality to send User Set control characters? If so, try various control characters from the ASCII character set. Character 26 is one that I've encountered numerous times with some controls. Make sure that your PC software is not set to "Not Send" control characters. This is a feature of some comms packages.

If your software can't explicitly send control characters, send me your email address via PM and I'll send you a file that contains this character that you can cut and paste onto the end of your file.

Regards,

Bill